2 stihlusa.com
California Proposition 65
WARNING
This product can expose you to chemicals including
gasoline engine exhaust, which is known to the State of
California to cause cancer and carbon monoxide, which
is known to the State of California to cause birth defects
or other reproductive harm. For more information go to
www.P65Warnings.ca.gov.
WARNING
Battery posts, terminals, and related accessories contain
lead and lead compounds, chemicals known to the State
of California to cause cancer and birth defects or other
reproductive harm. Wash hands after handling.
California Public Resource Code, Section 4442
WARNING
It is a violation of California Public Resource Code, Section
4442, to use or operate the engine on any forest-covered,
brush-covered or grass-covered land unless the exhaust
system is equipped with a spark arrester, as defined
in Section 4442, maintained in effective working order.
Other states or federal jurisdictions may have similar laws.
Contact an Authorized Service Dealer to obtain a spark
arrester designed for the exhaust system installed on this
engine.
3
Table of Contents:
General Information..............................................................4
Identifying Your Unit............................................................ 4
Operator Safety..................................................................... 5
Safety Alert Symbol and Signal Words............................ 5
Safety Decals and Symbols............................................. 5
Safety Instructions............................................................ 7
Slope Identification Guide.............................................. 13
Safety Interlock System..................................................13
Features and Controls........................................................14
Control Functions and Locations....................................14
Operation............................................................................. 16
Before First Time Operation...........................................16
Checks Before Starting.................................................. 16
Starting the Engine.........................................................16
Stopping the Zero-Turn Riding Mower........................... 16
Zero-Turn Riding Mower Driving Practice...................... 17
Mowing............................................................................18
Mowing Recommendations............................................ 18
Pushing the Unit by Hand.............................................. 20
Attaching a Trailer.......................................................... 21
Storage........................................................................... 22
Maintenance Schedule....................................................... 23
Maintenance Procedures................................................... 24
Service and Maintenance Safety................................... 24
Checking/Adding Fuel.................................................... 24
Replacing the Fuel Filter................................................ 24
Check Engine Oil Level..................................................25
Changing the Engine Oil and Filter................................ 25
Clean the Engine Compartment with Air and Water.......25
Engine Maintenance.......................................................26
Containing Spilled Fluids and Proper Disposal of
Waste..............................................................................26
Servicing the Exhaust System....................................... 26
Fuse Identification and Location.................................... 26
Servicing the Hydraulic System..................................... 26
Lubrication...................................................................... 27
Servicing the Mower Blades...........................................28
Seat And Ground Speed Control Lever Adjustments..... 30
Checking Tire Pressures................................................ 31
Cutting Height Adjustment..............................................31
Floor Pan Removal and Installation............................... 32
Neutral Adjustment......................................................... 32
Suspension Adjustment (if equipped).............................32
Parking Brake Adjustment..............................................33
Mower Deck Removal and Installation...........................33
Deck Leveling Adjustment..............................................33
Mower Deck Drive Belt Replacement............................ 35
Washing the Mower Deck.............................................. 36
Transmission Drive Belt Replacement........................... 37
Battery Maintenance.......................................................37
Troubleshooting.................................................................. 39
Troubleshooting the Zero-Turn Riding Mower................39
Troubleshooting Common Cutting Problems..................39
Specifications...................................................................... 41
Limited Warranty.................................................................42
4 stihlusa.com
General Information
Thank you for purchasingthis quality-built STIHL zero-
turn riding mower.We’re pleased that you’ve placed your
confidence in the STIHL brand.
The manuals included with this unitcontain safety information
to make you aware of the hazards and risks associated with
the unit and how to avoid them. This zero-turn riding mower
was designed to be used as described in the operator's
manual for finish cutting of established lawns and is not
intended for any other purpose. It is important that you read
and understand the instructions thoroughly before attempting
to start or operate this equipment.
Save these original instructions for future reference.
The images in this document are representative, and
are meant to complement the instructional copy they
accompany. Your unit may vary from the images
displayed.LEFTandRIGHTare as seen from the operator's
position.
Have your authorized STIHL servicing dealer show you how
to operate your zero-turn riding mower.
Do not lend or rent your unit without this operator's manual.
Allow only persons who have the proper training and fully
understand the information in this manual to operate the zero-
turn riding mower.
For further information, or if you do not understand any of
the instructions in this manual, please go to stihlusa.com or
contact your authorized STIHL servicing dealer.
Recycle all packaging, used oil, and batteries according to
applicable government regulations.
Identifying Your Unit
The following products are covered by this manual:
RZ 142.0 & RZ 152.0
The product identification tag (A, Figure 1) can be found in
the location as shown in Figure 1.
1
Record your model number, product serial number, engine
model number and engine serial number in the space
provided for easy access.
When contacting your authorized STIHL servicing dealer for
replacement parts, service or information you MUST have
these numbers.
Note:For the location of the engine identification numbers
refer to the engine operator’s manual.
PRODUCT REFERENCE DATA
Unit Model Number:
Unit Serial Number:
Dealer Name:
Date Purchased:
ENGINE REFERENCE DATA
Engine Make:
Engine Model:
Engine Type / Specification:
Engine Code / Serial Number:
5
Operator Safety
Safety Alert Symbol and Signal Words
The safety alert symbol identifies safety information
about hazards that can result in personal injury. A signal word
(DANGER, WARNING, or CAUTION) is used with the alert
symbol to indicate the likelihood and the potential severity of
injury. In addition, a hazard symbol may be used to represent
the type of hazard.
DANGER indicates a hazard which, if not avoided, will
result in death or serious injury.
WARNING indicates a hazard which, if not avoided,
could result in death or serious injury.
CAUTION indicates a hazard which, if not avoided,
could result in minor or moderate injury.
NOTICE indicates information considered important but not
hazard-related.
Safety Decals and Symbols
Read the safety decals before operating your unit. The
cautions and warnings are for your safety. Understand and
follow all safety decals to reduce the risk of a personal injury
or property damage.
WARNING
If any safety decals become worn or damaged and
cannot be read, order replacement decals from your
local authorized STIHL servicing dealer.
2
A. Part Number: WB01-967-7205 - Decal, Main Safety
B. Part Number: WB01-967-7200 - Decal,Danger, Cut
Hand/Foot
6 stihlusa.com
Decal, Main Safety
Part Number: WB01-967-7205
DANGER
Amputation hazard.
Rotating blades cut off arms and legs.
• Stop the mower when children or others are near.
Keep bystanders away.
• Do not carry riders (especially children) even with
the blades off. They may fall off or return for another
ride when you are not expecting it.
• Look down, behind and to the side before changing
directions and while backing.
DANGER
Loss of control and roll over
hazard
Operating on slopes can be hazardous and cause loss
of control and roll overs.
• Do not operate on slopes over 10 degrees.
• Avoid sudden turns or rapid speed changes.
• Reduce speed and use extreme caution on slopes.
• Avoid turning down slopes; if possible turn up
slopes.
• If machine stops forward motion on a slope, stop the
blades and drive slowly off the slope.
DANGER
Water, retaining walls, and drop-off
hazards.
Wheels dropping over edges may result in serious
injury, death or drowning.
• Do not operate down slope towards or near water,
retaining walls, or drop-offs.
• Give yourself a minimum of two mower widths of
clearance around these hazards.
WARNING
Fire hazard.
Gasoline is flammable. Yard debris is combustible.
• Allow engine to cool for at least 3 minutes before
refueling.
• Keep unit cleaned of yard debris.
• This equipment may create sparks that can start
fires around dry vegetation. A spark arrester may be
required. Contact local fire agencies for regulations
relating to fire prevention requirements.
7
WARNING
Avoid serious injury or death.
Read the operator's manual before using this product.
• Do not operate this machine unless you are trained.
• Know the location and function of all controls.
• Keep safety devices (guards, shields, switches, etc.)
in place and working. Wear eye and ear protection.
• Remove objects that could be thrown by the blade.
• Be sure blade(s) and engine are stopped before
placing hands or feet near blade(s).
• When leaving machine, shut off, remove key, and
set parking brake.
Decal, Danger, Cut Hand/Foot
Part Number: WB01-967-7200
DANGER
Keep hands and feet away from deck.
Do not operate mower unless discharge
chute or entire grass catcher is in its proper
place.
Safety Instructions
General Safety
WARNING
• Read, understand, and follow the instructions and
warnings in this manual and on the unit, engine, and
attachments before you operate this unit.
• Failure to read and follow these safety instructions could
result in loss of control of the unit, severe personal injury,
or death to you, or bystanders, or damage to property or
equipment. This mowing deck is capable of amputating
hands and feet and throwing objects.
• Do not operate this unit unless you have been trained.
The owner is responsible for training the users. Reading
and understanding this operator's manual is a way to train
yourself.
• If the operator(s) or mechanic(s) cannot read English it
is the owner’s responsibility to explain this material to
them. Other language translations of this manual may be
available. See your authorized STIHL servicing dealer.
• Power equipment is only as safe as the operator. If it is
misused, or not properly maintained, it can be dangerous.
The owner/user can prevent, and is responsible for,
accidents or injuries occurring to themselves, other
people, or property.
• Only let adults who are responsible, trained, familiar with
the instructions, and physically capable to operate the
unit.
• Never let children or untrained people operate or service
the unit. Local regulations may restrict the age of the
operator.
• Do not operate the unit while under the influence of
alcohol or drugs.
• Never use a smart phone, tablet, or other electronic
device while operating. Distracted operation can increase
the risk of accident or personal injury.
• Wear appropriate personal protective equipment such
as safety shoes, long pants, safety glasses, and ear
protection. Long hair, loose clothing or jewelry may get
tangled in moving parts.
• Use common sense, and think through what you are
doing. If you are not sure that the task you are about
to perform can be safely done with the equipment you
have chosen, ask a professional: contact your authorized
STIHL servicing dealer.
• Do not put hands or feet near rotating parts or under the
unit. Keep clear of the discharge opening at all times.
• Keep the unit in good working order. Replace worn or
damaged parts.
• Use full width ramps when you load and unload the unit
for transport.
• Use care with grass catchers or other attachments. These
can change the stability of the unit. See attachment or
accessory manual or contact your authorized STIHL
dealer for information on proper wheel weights or
counterweights.
• To help prevent fires, keep the unit free of grass, leaves,
or other unwanted material. Clean remaining oil or fuel
spillage. Remove fuel soaked debris and let the unit cool
before storage.
8 stihlusa.com
Read the Manual
WARNING
The operator's manual contains important safety information
you need tobe aware of, understand, and apply BEFORE
you operate your unit and DURING operation.
Safe operating techniques, an explanation of the product’s
features and controls, and maintenance information is
included to help you get the most out of your investment.
Read this operator's manual thoroughly before use and
follow all safety precautions. Improper use can cause
serious or fatal injury.
Children
WARNING
Tragic accidents can occur if the operator is not alert to the
presence of children.Do not allow children anywhere near
the area of operation.Children are often attracted to the
unit and the mowing activity. Never assume that children
will remain where you last saw them.If there is a risk that
children may enter the area where you are mowing, have
another responsible adult watch them.
• Keep children out of the mowing area and under the
watchful care of another responsible adult other than
the operator.
• Be alert and turn the unit off if children enter the area.
• Always look down, behind, and to the side for children
before changing directions and while backing.
• Before and during reverse operation, look behind and
down for small children.
• Never carry children, even with the blade(s) off. They
may fall off and be seriously injured or interfere with
safe unit operation. Children who have been given rides
in the past may suddenly appear in the mowing area for
another ride and be run over or backed over by the unit.
• Never allow children to operate the unit.
• Use care when approaching blind corners, shrubs,
trees, or other objects that may obscure vision.
Operation
WARNING
• Clear the operating area of any objects which could be
thrown by or interfere with operation of the unit.
• Only operate in daylight or good artificial light.The
LED lights supplied with the unit or as an accessory
contribute to visibility but are not considered good
artificial light suitable for night time mowing.
• Keep away from holes and hidden hazards.
• Do not operate on public roads.
• Never operate the unit without guards securely in
place. Be sure all interlocks are attached, adjusted, and
functioning properly.
• Stop the unit on level ground, disengage the PTO,
engage the parking brake, and shut off the engine
before leaving the operator’s position for any reason
including emptying the grass catchers or unclogging the
chute.
• Never carry passengers and keep pets and bystanders
away.
• Do not direct discharge material toward anyone. Avoid
discharging material against a wall or obstruction.
Material may ricochet back toward the operator. Stop
the blade(s) when crossing gravel surfaces or when you
are not mowing.
• Use care when approaching blind corners, shrubs,
trees, or other objects that may obscure vision.
• Do not change the engine governor setting or
overspeed the engine.
• To help prevent fires, keep the unit free of grass,
leaves, or other unwanted material. Clean remaining oil
or fuel spillage. Remove fuel soaked debris and let the
unit cool before storage.
Starting
WARNING
• Only operate in well ventilated areas.Exhaust gases
contain carbon monoxide, a deadly poison.
• Be sure all drives are in neutral and parking brake is
engaged before starting engine. Only start engine from
the operator’s position.
Mowing
WARNING
• Do not mow in reverse unless absolutely necessary.
Always look down, behind, and to the side before
changing directions and while backing.
• Do not direct discharge material toward anyone. Avoid
discharging material against a wall or obstruction.
Material may ricochet back towards the operator. Stop the
blade(s) when crossing gravel surfaces. Do not operate
9
the mower without either the entire grass catcher or the
deflector in place.
• Slow down and use caution when making turns and when
changing directions on slopes.
• Never raise deck with the blades running.
• Never leave a running unit unattended. Always disengage
the PTO, set parking brake, stop engine, and remove
keys before dismounting. Keep hands and feet away from
the blades.
• Turn off the PTO switch to disengage the blades when
not mowing.
• Never operate without guards securely in place. Be
sure all interlocks are attached, adjusted properly and
functioning properly.
• Never operate with the discharge deflector raised,
removed or altered, unless using a grass catcher.
• Stop on level ground, disengage the PTO, engage the
parking brake, shut off the engine before leaving the
operator’s position for any reason including emptying the
grass catchers or unclogging the chute.
• Stop equipment and inspect blades after striking objects
or abnormal vibration occurs. Make necessary repairs
before resuming operations.
• Keep hands and feet away from the blades.
Moving Parts
WARNING
This unit has many moving parts that can injure you or
someone else. Remain seated during operation and follow
the safety instructions in this operator's manual to reduce
the risk of injury.
The mower deck has spinning mower blades that can
amputate hands and feet. Do not allow anyone near the unit
while it is running. Keep safety devices (guards, shields,
and switches) in place and working.
This zero-turn riding mower is equipped with an operator
presence interlock system. Do NOT attempt to alter or
bypass the system. See your authorized STIHL servicing
dealer immediately if the system does not pass all the
safety interlock system tests found in this manual.
Check that operator’s presence controls, safety switches
and shields are attached and functioning properly. Do not
operate unless they are functioning properly.
Slope Operation
WARNING
Operation on slopes can be dangerous. Using the unit on
a slope that is too steep where you do not have adequate
wheel traction (and control) can cause sliding, loss of
steering, control, and possible roll over. Do not operate
the unit under any condition where traction, steering, or
stability is in question. Tires could slide even if the wheels
are stopped. Do not operate on a slope greater than 10
degrees (a 3.5 foot rise over a 20 foot length).
Avoid turning down slopes; if possible turn up slopes. Avoid
sudden turns or rapid speed changes. Reduce speed and
use extreme caution on ALL slopes.
The surface condition you are on can greatly impact your
ability to safely operate this unit. Operating on wet or
slippery slopes can cause sliding and loss of steering and
control. Do not operate on slopes that are slippery, wet, or
have soft soil conditions.
If you feel uncomfortable about operating the unit on a
slope, don’t do it.
WARNING
Slopes are a major factor related to loss-of-control and
tipover accidents, which can result in severe injury or death.
All slopes require extra caution. If you cannot back up the
slope or if you feel uneasy on it, do not drive on it.
Do not use this unit on slopes greater than 10 degrees.
Select slow ground speed before driving onto slope. Use
extra caution when operating on slopes with rear-mounted
grass catchers.
Avoid turning down slopes; if possible turn up slopes. Use
caution when changing direction and do not start or stop on
a slope.
Do:
• Remove obstacles such as rocks, tree limbs, etc.
• Evaluate the terrain to determine what accessories and
attachments are needed to properly and safely perform
the job. Use only accessories and attachments approved
by the manufacturer.
• Avoid holes, ruts, bumps, rocks, or other hidden hazards.
Uneven terrain could overturn the unit, or cause the
operator to lose their balance or footing. Tall grass can
hide obstacles.
• Slow down and use extra care on slopes. Be sure to
travel in the recommended direction on slopes. Turf
conditions can affect the unit's stability. Use caution when
operating near drop-offs.
• Slow down and use caution when making turns and when
changing directions on slopes.
• Use slow speed. Choose a slow speed so that you will
not have to stop or change speed while on the slope.
• Keep all movement on the slopes slow and gradual. Do
not make sudden changes in speed or direction.
10 stihlusa.com
• Use care with grass catchers or other attachments. These
can change the stability of the unit.See your attachment
or accessory manual or contact your authorized STIHL
dealer for information on proper wheelweights or
counterweights.
Do NOT:
• Avoid starting, stopping, or turning on a slope. Do NOT
make sudden changes in speed or direction, which could
cause the mower to roll over.
• Do not mow down slopes towards or near drop-offs,
ditches, or embankments. The mower could suddenly
turn over if a wheel is over the edge of a cliff or ditch, or if
an edge caves in. Give yourself a minimum of two mower
widths of clearance around these hazards.
• Do not mow on wet grass. Reduced footing or traction
could cause sliding.
• Do not try to stabilize the unit by putting your foot on the
ground.
• Do not mow excessively steep slopes.
• Do not use grass catcher on steep slopes.
• Do not mow slopes if you cannot back up them.
Retaining Walls, Drop-Offs, and Water
WARNING
Retaining walls and drop-offs around steps and water are
a common hazard. Do NOT operate down slope towards or
near water, retaining walls, or drop-offs.
WARNING
Give yourself a minimum of two mower widths of clearance
around these hazards and hand-trim with a walk behind
mower or string trimmer. Wheels dropping over retaining
walls, edges, ditches, embankments, or into water can
cause rollovers, which may result in serious injury, death, or
drowning.
Thrown Objects
WARNING
This unit has spinning mower blades. These blades can
pick up and throw debris that could seriously injure a
bystander. Clear the operating area of any objects which
could be thrown by, or interfere with operation of, the unit.
Do not operate the unit without the entire grass catcher,
discharge chute, or other safety devices in place and
functioning properly. Check frequently for signs of wear or
deterioration and replace as needed.
Do not allow anyone in the area while the unit is running. If
someone enters the area, shut the unit off immediately, and
wait until they leave to re-start the unit.
Fuel and Maintenance
11
WARNING
Always disengage all drives, shut off the engine, and
remove the key before doing any cleaning, refueling, or
servicing.
Fuel and its vapors are extremely
flammable. Do not smoke while operating or
fueling. Do not add fuel while engine is hot
or running. Allow engine to cool for at least
three (3) minutes prior to adding fuel.
Do not add fuel indoors, in an enclosed trailer, garage, or
any other enclosed area that is not well ventilated. Fuel
spills should be cleaned up promptly and before operation
begins.
Fuel should be stored only in sealed containers approved
for fuel.
Proper maintenance is critical to the safety and
performance of your unit. Keep the unit free of grass,
leaves, and excess oil. Be sure to perform the maintenance
procedures listed in this manual, especially periodically
testing the safety system.
WARNING
To avoid personal injury or property damage, use extreme
care in handling fuel. Fuel is extremely flammable and the
vapors are explosive.
• Extinguish all cigarettes, cigars, pipes, and other sources
of ignition.
• Use only approved fuel containers.
• Never remove the fuel cap or add fuel with the engine
running or while hot. Allow the engine to cool for three (3)
minutes before adding fuel.
• Never add fuel to, or drain fuel from, the unit indoors.
• Never store the unit or fuel container where there is an
open flame, spark, or pilot light such as near a water
heater or other appliance.
• Never fill fuel containers inside a vehicle or on a truck bed
with a plastic bed liner. Always place containers on the
ground away from your vehicle before filling.
• Remove fuel-powered equipment from the truck or
trailer and refuel it on the ground. If this is not possible,
then refuel such equipment on a trailer with a portable
container, rather than from a fuel dispenser nozzle.
• Keep nozzle in contact with the rim of the fuel tank or
container opening at all times until fueling is complete. Do
not use a nozzle lock-open device.
• If fuel is spilled on clothing, change clothing immediately.
• Never over-fill the fuel tank. Replace fuel cap and tighten
securely.
• Use care in handling fuels. They are flammable and
vapors are explosive.
• If fuel is spilled, do not attempt to start the engine but
move the unit away from the area of spillage and avoid
creating any source of ignition until fuel vapors have
dissipated.
• Replace all fuel tank caps and fuel container caps
securely.
WARNING
• Keep all hardware, especially blade attachment bolts,
tight and keep all parts in good working condition.
Replace all worn or damaged parts.
• Never tamper with safety devices. Check their proper
operation regularly.
• Disengage the PTO, set the parking brake, stop the
engine and remove the ignition key and/or disconnect
spark plug wire. Wait for all movement to stop before
adjusting, cleaning, or repairing.
• Clean grass and debris from mower deck, drives,
mufflers, and engine to prevent fires. Clean up oil or fuel
spillage.
• Stop and inspect the equipment if you strike an object.
Repair, if necessary, before restarting.
• Park the unit on level ground. Never allow untrained
personnel to service the unit.
• Use jack stands to support components when required.
• Carefully release pressure from components with stored
energy.
• Disconnect the battery cables or remove the spark
plug wire(s) before making any repairs. Disconnect the
negative terminal first and the positive last. Reconnect
positive first and negative last.
• Use care when checking blades. Wrap the blade(s) with
a shop towel or wear gloves, and use caution when
servicing them. Only replace blades. Never straighten or
weld them.
• Keep hands and feet away from moving parts. If possible,
do not make adjustments with the engine running.
• Charge batteries in an open, well ventilated area, away
from spark and flames. Unplug the charger before
connecting or disconnecting from the battery. Wear
protective clothes and use insulated tools.
• Grass catcher components are subject to wear, damage,
and deterioration, which could expose moving parts or
allow objects to be thrown. Frequently check components
and replace with manufacturer’s recommended parts,
when necessary.
• Check brake operation frequently. Adjust and service as
required.
• Use only STIHL recommended replacement parts when
making repairs.
• Always comply with factory specifications on all settings
and adjustments.
• Only authorized STIHL servicing dealers should be
utilized for major service and repair requirements.
• Never attempt to make major repairs on this unit unless
you have been properly trained. Improper service
procedures can result in hazardous operation, equipment
damage and voiding of manufacturer’s warranty.
12 stihlusa.com
WARNING
Units with hydraulic pumps, hoses, or motors: Hydraulic
fluid escaping under pressure may have sufficient force to
penetrate skin and cause serious injury. If foreign fluid is
injected into the skin it must be surgically removed within
a few hours by a doctor familiar with this form of injury or
gangrene may result. Keep body and hands away from
pin holes or nozzles that eject hydraulic fluid under high
pressure. Use paper or cardboard, and not hands, to search
for leaks. Make sure all hydraulic fluid connections are tight
and all hydraulic hoses and lines are in good condition
before applying pressure to the system. If leaks occur, have
the unit serviced immediately by your authorized STIHL
servicing dealer.
WARNING
Stored energy device. Improper release of springs can
result in serious personal injury. Springs should be removed
by an authorized STIHL servicing dealer.
WARNING
Units equipped with an engine radiator: Stored energy
device. To prevent serious bodily injury from hot coolant or
steam blow-out, never attempt to remove the radiator cap
while the engine is running. Stop the engine and wait until it
is cool. Even then, use care when removing the cap.
Enclosed Areas
WARNING
Only operate this unit outdoors and away from unventilated
areas such as inside enclosed trailers and garages.
The engine emits poisonous carbon monoxide gas and
prolonged exposure in an enclosed area can result in
serious injury or death.
Towed Equipment
WARNING
• Tow only with a unit that has a hitch designed for
towing. Do not attach towed equipment except at the
hitch point.
• Follow the manufacturer’s recommendations for weight
limit for towed equipment and towing on slopes. See
Attaching a Trailer under OPERATION.
• Never allow children or others in or on towed
equipment.
• On slopes, the weight of the towed equipment may
cause loss of traction and loss of control.
• Travel slowly and allow extra distance to stop.
• Do not shift to neutral and coast down hill.
Emissions
WARNING
• Engine exhaust from this product contains chemicals
known, in certain quantities, to cause cancer, birth
defects, or other reproductive harm.
• Look for the relevant Emissions Durability Period and
Air Index information on the engine emissions label.
Hearing Protection
WARNING
OSHA regulations may require the use of hearing protection
when exposed to sound levels greater than 85 dBA for an 8
hour time period.
This unit produces sound levels in excess of 85 dBA at the
operator’s ear and can cause hearing loss though extended
periods of exposure.
Wear ear and eye protection when operating this unit.
13
Slope Identification Guide
3
How to measure the slope of a lawn surface with a
smartphone or an angle finder tool:
WARNING
To reduce the risk of serious personal injury or death, never
operate on slopes greater than 10 degrees.
1. Use a straight edge at least two (2) feet long (A, Figure
3). A 2x4 or a straight piece of metal works well.
2. Angle finder tools:
a. Use your smartphone: Many smartphones (B,
Figure 3) have an inclinometer (angle finder) located
under the compass application (app). Or, search an
app store for an inclinometer app.
b. Use angle finder tools: Angle finder tools (C and
D, Figure 3) are available at local hardware stores
or online (also called inclinometer, protractor, angle
meter, or angle gauge). Dial type (C) or digital type
(D) work, others may not. Read and obey the user
instructions supplied with the angle finder tool.
3. Put the two (2) feet long straight edge along the steepest
part of the lawn slope. Put the board up and down the
slope.
4. Lay the smartphone or angle finder tool on the straight
edge and read the angle in degrees. This is the slope of
your lawn.
Note:A paper gauge slope identification guide is included in
your product literature packet.
Safety Interlock System
WARNING
DO NOT operate unit if any safety interlock or safety
device is not in place and functioning properly. Contact
your authorized STIHL servicing dealer immediately for
assistance. DO NOT attempt to defeat, modify, or remove
any safety device.
Operational SAFETY Checks
Test 1 - Engine MUST NOT crank if:
• PTO switch is engaged, OR;
• Ground speed control levers are not locked in their
START/PARK positions.
Test 2 - Engine SHOULD crank if:
• PTO switch is NOT engaged, AND;
• Ground speed control levers are locked in their START/
PARK positions.
Test 3 - Engine MUST SHUT OFF if:
• Operator rises off seat with PTO engaged, OR;
• Operator rises off seat ground speed control levers not
locked in their START/PARK positions.
Test 4 - Blade Brake Check
The mower blades and mower drive belt should come to
a complete stop within five (5) seconds after electric PTO
switch is turned off (or operator rises off the seat). If mower
drive belt does not stop within five (5) seconds, see your
authorized STIHL servicing dealer.
Note:Once the engine is stopped, the PTO switch must
be turned off and the ground speed control levers must be
locked in their START/PARK positions in order to start the
engine.
14 stihlusa.com
Features and Controls
Control Functions and Locations
The information below briefly describes the function of
individual controls. Starting, stopping, driving, and mowing
require the combined use of several controls applied in
specific sequences. To learn what combination and sequence
of controls to use for various tasks see the OPERATION
section.
Zero-Turn Riding Mower Controls
4
A. Deck Lift Pedal, Cutting Height Adjustment Pin, and
Deck Lift Lock Lever
B. Removable Floor Plate
C. ThrottleControl
D. Hour Meter
E. PTO (Power Take Off) Switch
F. Ignition Switch
G. Transmission Oil Fill/Tanks (One per transmission if
equipped)
H. Transmission Release Levers (One per transmission)
I. Fuel Level Gauge (if equipped)
J. Fuel Tank Cap
K. Seat Adjustment Hardware
L. Dual USB Charging Port (if equipped)
M. Deck Washout Port
N. Left Ground Speed Control Lever
O. Right Ground Speed Control Lever
Deck Lift Pedal, Cutting Height Adjustment Pin, and Deck
Lift Lock Lever: These controls are used to adjust the cutting
height of the mower deck.
Depress the deck lift pedal (A, Figure 5) until the deck lift
lock lever (B) locks the mower deck into the 4-1/2" (11,4 cm)
TRANSPORT position. Place the cutting height adjustment
pin (C) into the hole for the desired cutting height. Depress
the deck lift pedal, move the deck lift lock lever outwards,
and slowly release the deck lift pedal until it rests against the
cutting height adjustment pin.
5
Cutting Height Adjustment
Pin
Deck Lift Lock Lever
Removable Floor Plate: The floor plate can be removed for
easy access to the mower deck. To remove the plate, remove
the retainer hardware and tilt the floor pan up and then
remove from the unit. Reverse the process for re-installation.
Throttle Control: The throttle controls engine speed. Move
the throttle forward to increase engine speed and back to
decrease engine speed. Always operate at FULL throttle
when mowing.
Fast throttle speed. Slow throttle speed.
15
Hour Meter: This unit is equipped with an hour
meter that records the number of hours that the engine has
been run.
PTO (Power Take Off) Switch: The PTO switch
engages and disengages the mower blades. Pull UP on the
switch to engage, and push DOWN to disengage.
Ignition Switch: The ignition switch starts and stops the
engine, it has three positions:
OFF: Stops the
engine and shuts
off the electrical
system.
RUN: Allows the
engine to run
and powers the
electrical system.
START: Cranks
the engine for
starting.
Note:Never leave the ignition switch in the RUN position with
the engine stopped—this drains the battery.
Transmission Oil Fill: Transmission oil is added through the
hydraulic oil tanks. It also serves as extra holding capacity
for oil as the transmissions heat up and the hydraulic oil
expands. See Check / Fill Transmission Oil for oil level check
and fill procedures.
Transmission Release Levers:
Symbol Control Name
Transmission Release Levers
Transmission Release Levers
(Models with Suspension)
Each transmission is equipped with a transmission release
lever. These levers deactivate the transmissions so that the
unit can be pushed by hand. Both transmission release levers
must be in the same position whether you are driving the
unit or pushing it by hand. See Pushing the Unit by Hand for
operational information and control location.
Fuel Level Gauge: Displays the fuel level in the
tank.
Fuel Tank Cap: To remove the cap, turn counter-clockwise.
Seat Adjustment Hardware: The position of the seat can be
adjusted forwards or backwards to meet the comfort needs
of the operator. See Seat Adjustment for instructions on
adjusting the seat position.
Dual USB Charging Port: Open the top doors to access the
two (2) USB charging ports. The USB port provides a total
current of up to 3.15 amps and its center LED indicates when
charging is in process.The ignition switch must be in the
RUN position for charging.
Deck Washout Port: The washout port allows you to connect
a typical garden hose to the left-hand side of the mower deck
to remove grass and debris from the underside. See Washing
the Mower Deck for instructions on how to use the washout
port.
Ground Speed Control Levers: These levers control the
ground speed and direction of the zero-turn riding mower.
A. Forward
B. Neutral
C. Reverse
D. Parking Brake Engaged
The left lever controls the left rear drive wheel and the right
lever controls the right rear drive wheel and engages the
parking brake.
Moving a lever forward from the NEUTRAL position (A)
increases the FORWARD (B) speed of the associated wheel
and pulling back on a lever increases the REVERSE (C)
speed.
Tilting the ground speed control levers outwards from the
NEUTRAL position will engage the parking brake (D). Tilting
the ground speed control levers in towards the NEUTRAL
position will disengage the parking brake.
Note:The further a lever is moved away from the neutral
position, the faster the drive wheel will turn.
See the Zero-Turn Riding Mower Driving Practice section for
steering instructions.
16 stihlusa.com
Operation
Before First Time Operation
• Be sure to read all information in the OPERATOR
SAFETY and OPERATION sections before attempting to
operate this unit.
• Become familiar with all of the controls and how to stop
the unit.
• Drive in an open area without mowing to become
accustomed to the unit.
WARNING
• Never operate on slopes greater than 10 degrees.
• Select slow ground speed before driving onto a slope.
Use extra caution when operating on slopes with a rear-
mounted grass catcher.
• Avoid turning down slopes; if possible turn up slopes.
Use caution when changing direction on slopes and do
NOT start or stop on a slope.
WARNING
• Never allow passengers to ride on the unit.
• Before leaving the operator’s position for any reason,
engage the parking brake, disengage the PTO, stop the
engine and remove the key.
• To reduce fire hazard, keep the engine and zero-turn
riding mower free of grass, leaves, and excess grease.
Do NOT stop or park unit over dry leaves, grass or
combustible materials.
• Fuel is highly flammable and must be handled with
care. Do NOT remove the fuel cap(s) or add fuel with
the engine running or while hot. Do NOT allow open
flame, smoking, or matches in the area. Avoid over-
filling and wipe up any spills.
WARNING
Do NOT load this zero-turn riding mower on a trailer or truck
using two separate ramps. Only use a single ramp that is at
least one foot wider than the width of the rear wheels of this
unit. This unit has a zero turning radius and the rear wheels
could fall off the ramps, or the unit could tip over injuring the
operator or bystanders.
Checks Before Starting
• Check that the crankcase is filled to the full mark on
the crankcase oil fill and dipstick. If necessary, add oil
through the engine oil fill. See the engine operator’s
manual for instructions, engine oil dipstick location, and
oil recommendations.
• Make sure that all nuts, bolts, screws, and pins are in
place and tight.
• Adjust the seat position and make certain you can reach
all of the controls from the operator’s position.
• Fill the fuel tank with fresh fuel. Refer to the engine
operator’s manual for fuel recommendations.
• Suspension units only: Check the hydraulic oil level.
Starting the Engine
WARNING
• If you do not understand how a specific control
functions, or have not yet thoroughly read the
FEATURES AND CONTROLSsection, do so now.
• Do NOT attempt to operate the unit without first
becoming familiar with the location and function of all
controls.
1. While sitting in the operator's seat, make sure that the
PTO switch is disengagedand the ground speed control
levers are locked in the START/PARK position.
Note:The parking brake is automatically engaged when the
ground speed control levers are locked in the START/PARK
position.
2. Set the throttle control to the FAST position.
Note:This engine is equipped with a ReadyStart® feature
and does not require a manual choke lever.
3. Insert the key into the ignition switch and turn it to
START.
4. After the engine starts, reduce to half throttle speed and
allow the engine to warm. Warm up the engine by running
it for at leasta minute before engaging the PTO switch or
driving the unit.
5. After warming the engine always operate the unit at the
FAST throttle position when mowing.
In the event of an emergency the engine can be stopped
by simply turning the ignition switch to OFF. Use this
method only in emergency situations. For normal engine shut
down follow the procedure given in Stopping the Zero-Turn
Riding Mower.
Stopping the Zero-Turn Riding Mower
1. Drive the unit to a flat, level surface and return the ground
speed control levers to the middle (NEUTRAL) position
to stop the unit's movement. Pivot the levers outward
to lock them in the START/PARK position. This action
automatically engages the parking brake.
2. Disengage the PTO by pushing down on the PTO
switch.Move the throttle control to the SLOW position
and turn the ignition switch to OFF. Remove the key.
17
Zero-Turn Riding Mower Driving Practice
Before attempting to drive the zero-turn riding mower
make sure you have read the FEATURES AND
CONTROLSsection and understand the location and function
of all of the unit’s controls.
The ground speed control levers of this zero-turn riding
mower are responsive, and learning to gain a smooth and
efficient control of the unit’s forward, reverse, and turning
movements will take some practice.
Before you begin mowing, spend some time going through
the maneuvers shown in this manual and become familiar
with how the unit accelerates, travels, and steers.
Locate a smooth, flat area of your lawn with plenty of room
to maneuver. Clear the area of objects, people, and animals
before you begin. Operate the unit at mid-throttle during
this practice session (ALWAYS operate at full throttle when
mowing), and turn slowly to prevent tire slippage and damage
to your lawn.
We suggest you begin with the Smooth Travel procedure,
and then advance through the forward, reverse, and turning
maneuvers.
Smooth Travel
The ground speed control levers of the zero-turn riding mower
are responsive.
The BEST method of handling the ground speed control
levers is in three steps — as shown in Figure 6.
6
FIRST,place your hands onto the levers as shown.
SECOND, to go forward gradually push the levers forward
with your palms.
THIRD, to speed up move the levers farther forward. To slow
down smoothly, slowly move the levers toward neutral.
Basic Driving
Forward Travel Practice
7
Gradually move both ground speed control levers — evenly
FORWARD from neutral. Slow down and repeat.
Note:Straight forward travel takes practice. If necessary, top
speed can be balance-adjusted — see the Speed Balancing
Adjustment in the MAINTENANCE PROCEDURES section of
this manual.
Reverse Travel Practice
8
LOOK DOWN AND BEHIND, then gradually move both
ground speed control levers evenly BACK from neutral. Slow
down and repeat.
Note:Practice backing up for several minutes before
attempting to do so near objects. The zero-turn riding mower
turns sharply in reverse as well as forward, and backing up
straight takes practice.
Practice Turning Around A Corner
18 stihlusa.com
9
While traveling forward allow one ground speed control lever
to gradually return back toward neutral. Repeat several times.
Note:To prevent pivoting directly on the tire tread, it is best to
keep both wheels going at least slightly forward.
Practice Turning in Place
10
To turn in place, “zero-turn,” gradually move one ground
speed control lever forward from neutral and the other lever
back from neutral simultaneously. Repeat several times.
Note:Changing the amount each ground speed control lever
is pulled—forward or back, changes the “pivot point” you turn
on.
Advanced Driving
Executing an End-Of-Row Zero-Turn
11
Your zero-turn riding mower's unique ability to turn in place
allows you to turn around at the end of a cutting row rather
than having to stop and Y-turn before starting a new row.
For example, to execute a left end-of row zero turn:
1. Slow down at the end of the row.
2. Move the RIGHT ground speed control lever forward
slightly while moving the LEFT ground speed control lever
back to center and then slightly back from center.
3. Begin mowing forward again.
This technique turns the unit LEFT and slightly overlaps the
row just cut — eliminating the need to back up and re-cut
missed grass.
Mowing
1. Make sure that the PTO switch is disengaged, the ground
speed control levers are locked in their START/PARK
positions, and the operator is in the seat.
2. Start the engine. See Starting the Engine.
3. See the mower cutting height. See Cutting Height
Adjustment.
4. Set the throttle to the 1/2 throttle position
Note:It is best practice to engage the PTO with the throttle
set at the minimum throttle position necessary to engage the
deck drive system without stalling the engine.
5. Engage the PTO by pulling up on the PTO switch.
6. Move the throttle to the FAST position and pivot the
ground speed control levers in from the START/PARK
position to the neutral “N” position.
7. Begin mowing.
8. When finished, reduce throttle speed so that the engine
idles and push the PTO switch down to shut off the PTO.
9. Stop the engine. See Stopping the Zero-Turn Riding
Mower.
Mowing Recommendations
Several factors can affect how well your unit cuts grass,
Following proper mowing recommendations can improve the
performance and life of your unit.
19
Height of Grass
Often cutting height is a matter of personal preference.
Typically, you should mow the grass when it is between three
and five inches high. The proper cutting height range for
a specific lawn will depend upon several factors, including
the type of grass, the amount of rainfall, the prevailing
temperature, and the lawn’s overall condition.
Cutting the grass too short causes weak, thin grass plants,
which are easily damaged by dry periods and pests. Cutting
too short is often more damaging than allowing the grass to
be slightly higher.
Letting grass grow a bit longer—especially when it is hot and
dry—reduces heat build-up, preserves needed moisture and
protects the grass from heat damage and other problems.
However, allowing grass to grow too high can cause thin turf
and additional problems.
Cutting off too much at one time shocks the plant’s growth
system and weakens the grass plants. A good rule of thumb
is the 1/3 rule: to cut no more than one third of the grass
height, and never more than 1 inch at a time.
12
The amount of grass you are able to cut in one pass is also
effected by the type of mowing system you are using (for
example, broadcasting with side discharge decks can process
a much larger volume of grass than mulching does).
Tall grass requires incremental cutting. For extremely tall
grass, set the cutting height at maximum for the first pass (A,
Figure 13), and then reset it to the desired height and mow a
second (B) or third time.
Don’t cover the grass surface with a heavy layer of clippings.
Consider using a grass collection system and starting a
compost pile.
13
When and How Often to Mow
The time of day and condition of the grass greatly affect the
results you’ll get when mowing. For the best results, follow
these guidelines:
• Mow when the grass is between three and five inches
high.
• Mow with sharp blades. Short clippings of grass one inch
or shorter decompose more quickly than longer blades.
Sharp mower blades cut grass cleanly and efficiently,
preventing frayed edges which harm the grass.
• Mow at time of day when the grass is cool and dry. Late
afternoon or early evening often provide these ideal
mowing conditions.
• Avoid mowing after rain or even heavy dew, and never
mulch when the grass is wet (moist grass does not mulch
well, and clumps beneath the mower deck).
Mowing Patterns
Always start mowing on a smooth, level area.
The size and type of area to be mowed will determine the
best mowing pattern to use. Obstructions such as trees,
fences and buildings, and conditions such as slopes and
grades must also be considered.
• Cut long straight strips overlapping slightly.
• Where possible, change patterns occasionally to
eliminate matting, graining or a corrugated appearance.
• For a truly professional cut, mow across the lawn in one
direction, then re-cut the lawn by mowing perpendicular to
the previous cut.
Note:Always operate the engine at FULL THROTTLE when
mowing.
If you hear the engine slowing down, you are mowing too
fast—using a slower ground speed will improve the cutting
efficiency of the blades and prevents many common cutting
problems. Use an appropriate ground speed for the thickness
and height of the grass you are cutting (3rd gear or slower for
manual gear models). If you hear the engine slowing down
you are mowing too fast, use a slower ground speed.
20 stihlusa.com
14
Where possible, make one or two passes around the outside
of the area discharging the grass INTO the lawn to keep the
cut grass off fences and walks.
15
The remainder of the mowing should be done in the opposite
direction so that the clippings are dispersed OUT onto the
area of lawn previously cut.
Mowing Methods
Broadcast Mowing
Broadcasting, or side-discharging, disperses fine clippings
evenly over the entire lawn. Many golf courses use this
method. Your mower has a deep dish deck to allow freer
circulation of clippings so they are broadcast evenly over the
lawn.
Engine Speed & Ground Speed for Broadcasting:
Always operate the engine at full throttle when mowing.
If you hear the engine slowing down, you are mowing too
fast—using a slower ground speed will improve the cutting
efficiency of the blades and prevents many common cutting
problems.
ALWAYS use an appropriate ground speed for the thickness
and height of the grass you are cutting (3rd gear or slower for
manual gear models). If you hear the engine slowing down
you are mowing too fast, use a slower ground speed.
How Much Grass to Cut Off When Broadcasting:
Mow when the grass is 3-5 inches long. Do not cut the grass
shorter than 2 to 2-1/2 inches. Do not cut off more than 1 inch
of grass in a single pass.
Mulching
Mulching consists of a mower deck which cuts and re-cuts
clippings into tiny particles and which then blows them down
INTO the lawn. These tiny particles decompose rapidly
into by-products your lawn can use. UNDER PROPER
CONDITIONS, your mulching mower will virtually eliminate
noticeable clippings on the lawn surface.
Note:When mulching under heavy cutting conditions, a
rumbling sound may be present and is normal.
Mulching Requires EXCELLENT Mowing Conditions:
Mulching mowers cannot function properly if the grass is
wet, or if the grass is simply too high to cut. Even more than
normal mowing, mulching requires that the grass be dry and
the appropriate amount is cut.
Do not use the mower as a mulching mower during the
first two or three mowings in the spring. The long grass
blades, quick growth, and often wetter conditions are more
suitable for broadcasting (side-discharging) or grass bagging
operation.
Engine Speed & Ground Speed for Mulching:
Use full engine throttle matched with a slow ground speed so
that clippings will be finely cut. Ground speed while mulching
should be HALF of the speed that would be used when
broadcasting (side discharging) under similar conditions.
Since mulching requires more horsepower than broadcasting,
using a slower ground speed is vitally important for proper
mulching operation.
How Much Grass to Mulch:
The best mulching action typically results from cutting only
the top 1/2 inch to 3/4 inch of grass blade. This provides
short clippings which decompose properly (much more
quickly than longer clippings). The ideal cutting height will
vary with climate, time of year, and quality of your lawn. We
recommend that you experiment with both the cutting height
and ground speed until you achieve the best cut. Start with
a high cutting height and using progressively lower settings
until you find a cutting height that is matched to your mowing
conditions and preferences.
Pushing the Unit by Hand
WARNING
Unsafe Operation Hazard.
DO NOT disengage the transmissions and coast down
slopes. DO NOT use transaxle release levers to disengage
the transmissions unless the unit’s motion can be controlled
and the engine is off.
NOTICE
Do not tow unit. Towing the unit will cause transmission
damage. Do not use another vehicle to push or pull this unit.
1. Disengage the PTO, lock the ground speed control levers
into their START/PARK positions, turn the ignition switch
to OFF, remove the key, and wait for all moving parts to
stop.
21
2. Locate the transmission release levers on the rear of the
unit.
• Non-suspension Models: The transmission release
levers (A, Figure 16) are located on the sides of the
bumpers.
• Suspension Models: The transmission release
levers (B) are located on the rear of the unit beneath
the bumper.
16
There is one transmission release lever on each
transmission. The transmission release levers open and
close the transmission bypass valves.
3. To open the transmission bypass valves (bypass
position):
• Non-suspension Models: Pull the transmission
lever towards the rear of the unit, then up in the
slot, and allow it to rest in the notch (C). Repeat this
process for the other side of the unit.
• Suspension Models: Pull the transmission release
lever out towards the rear of the unit and then
towards the center of the unit (D). Repeat this
process for the other side of the unit.
4. Pivot the ground speed control levers in from the START/
PARK position to the neutral ‘N’ position to disengage the
parking brake. The unit can now be pushed by hand.
5. After moving the unit, close the bypass valve (run
position):
• Non-suspension Models: Pull the transmission
release lever towards the rear of the unit, then down
in the slot, and then push it towards the front of the
unit (E). Repeat the process for the other side of the
unit.
• Suspension Models: Pull the transmission release
lever out towards the side of the unit and then push
forward (F). Repeat this process for either side of the
unit.
Note:Both transmission release levers must be in the same
position.
Attaching a Trailer
Secure the trailer with an appropriately sized clevis pin
(A, Figure 17) and clip (B). See OPERATOR SAFETYfor
additional safety information regarding towed equipment and
towing.
WARNING
Towing Hazard
Towed loads can be hazardous and cause loss of control
on slopes.
The surface being driven on greatly impacts traction and
stability. Wet or slippery surfaces can greatly reduce
traction and the ability to stop or turn. Carefully evaluate
the surface conditions before operating the unit with towed
equipment.
• The maximum gross (trailer & load) weight of the trailer
should not exceed 200 lbs (91 kg).
• The maximum tongue weight should not exceed 20 lbs
(9,1 kg).
• Do not operate on slope exceeding 5 degrees.
• Reduce speed and use extreme caution on slopes.
• Do not tow with a grass bagger attached.
17
Excessive towed loads can cause loss of traction and loss of
control on slopes. Reduce towed weight when operating on
slopes. The surface being driven on greatly impacts traction
and stability. Wet or slippery surfaces can greatly reduce
traction and the ability to stop or turn. Carefully evaluate the
surface conditions before operating the unit and trailer, and
never operate on slopes greater than 5°.
22 stihlusa.com
Storage
WARNING
Fuel and Explosion Hazard
Never store the unit (with fuel) in a closed structure without
sufficient airflow. Fuel vapors can travel to an ignition
source (such as a furnace, water heater, etc.) and cause an
explosion. Fuel vapor is also toxic to humans and animals.
When Storing Fuel Or Equipment With Fuel in Tank
• Store away from furnaces, stoves, water heaters, or
other appliances that have pilot lights or other ignition
sources because they can ignite fuel vapors.
Equipment
Disengage the PTO, lock the ground speed control levers in
the START/PARK position, turn the ignition switch to OFF,
and remove the key.
Battery life will be increased if it is removed. Put in a cool, dry
place and keep fully charged during storage. If the battery is
left in the unit, disconnect the negative cable.
Clean all debris from the unit and the engine compartment.
Apply paint or rust preventative to any areas where paint is
chipped or damaged.
Engine and Engine Oil
While the engine is still warm, change the engine oil.
Follow all storage instructions described in the engine
operator's manual that was included with your unit.
Before starting the unit after it has been stored:
• Check all fluid levels. Check all maintenance items.
• Do all recommended checks and procedures found in
this manual and the engine operator's manual that was
included with your unit.
• Let the engine warm up for several minutes before use.
23
Maintenance Schedule
The following schedule should be followed for normal care
of your unit. You will need to keep a record of your operating
time. Determining operating time is easily accomplished by
observing the hour meter.
For engine maintenance schedules and procedures, please
refer to the engine operator's manual.
UNIT MAINTENANCE
Every 8 Hours or Daily.*
Check the safety interlock system.
Clean debris off unit.**
Every 25 Hours or Annually.*
Check mower blade stopping time.
Check unit for loose hardware.
Check tire pressure.
Every 50 Hours or Annually.*
Check the unit's brakes.
Clean battery and cables.
See your Authorized STIHL Servicing Dealer Annually to:
Lubricate the unit.
Check mower blades**
* Whichever comes first.
** More often in hot (over 85° F; 30° C) weather or dusty operating
conditions.
ENGINE MAINTENANCE
Every 8 Hours or Daily*
Check engine oil level.
Clean debris from engine compartment.**
Every 50 Hours
Check/Clean spark arrester.***
Refer to the Engine Operator's Manual:
Service air filter.
Change engine oil and filter.
Check/Replace spark plugs.
Check/Replace fuel filter.
* Whichever comes first.
** More often in hot (over 85° F; 30° C) weather or dusty operating
conditions.
*** If equipped, replace if damaged.
24 stihlusa.com
Maintenance Procedures
Service and Maintenance Safety
WARNING
Amputation and crushing hazard
Specific steps must be taken in order to perform service and
maintenance procedures safely.
Read and follow all the applicable safety and instructional
messages in this manual.
Always disengage the mower blades, set the parking brake,
turn the engine OFF, remove the ignition key, and wait
for all movement to stop prior to performing service and
maintenance procedures.
Always disconnect the spark plug wire(s) and fasten it away
from the plug before beginning any maintenance or service
procedures in order to prevent accidental ignition.
Wear appropriate personal protective equipment such as
safety shoes, safety glasses, gloves, and ear protection.
Long hair, loose clothing or jewelry may get tangled in
moving parts.
Use of parts that are not authorized or approved by STIHL
may cause serious or fatal injury or property damage.
• STIHL recommends that only authorized STIHL
replacement parts be used for repair or maintenance.
Checking/Adding Fuel
WARNING
Fuel and its vapors are extremely flammable and
explosive.
Fire or explosion can cause severe burns or death.
When Adding Fuel
• Turn engine off and let engine cool at least 3 minutes
before removing the fuel cap.
• Extinguish all cigarettes, cigars, pipes, and other
sources of ignition.
• Fill fuel tank outdoors or in a well-ventilated area.
• Do not overfill fuel tank. To allow for expansion of the
fuel, do not fill above the bottom of the fuel tank neck.
• Keep fuel away from sparks, open flames, pilot lights,
heat, and other ignition sources.
• Check fuel lines, tank, cap, and fittings frequently for
cracks or leaks. Replace if necessary.
• If fuel spills, wait until it evaporates before starting
engine.
1. Clean the fuel cap area of dirt and debris. Remove the
fuel cap (A, Figure 18).
18
2. Fill the fuel tank with fuel. To allow for expansion of the
fuel, do not fill above the bottom of the fuel tank neck (B).
3. Reinstall the fuel cap.
NOTICE
Refer to your engine operator's manual for specific fuel
recommendations.
Replacing the Fuel Filter
WARNING
Fuel and its vapors are extremely flammable and
explosive.
Fire or explosion can cause severe burns or death.
Do NOT remove the fuel filter when the engine is hot, as
spilled gasoline may ignite. Do NOT spread hose clamps
further than necessary. Ensure clamps grip hoses firmly
over filter after installation.
The fuel filter (A, Figure 19) is located in the fuel line (B)
between fuel tank and carburetor, near the fuel pump.
19
25
If filter is dirty or clogged, replace as follows:
1. Disconnect the negative battery cable.
2. Place a container below the filter to catch spilled fuel.
3. Using pliers, open and slide the hose clamps away from
the fuel filter.
4. Remove hoses from filter.
5. Install new filter in proper flow direction in fuel line.
6. Secure with hose clamps.
7. Connect the negative battery cable when finished.
Check Engine Oil Level
Interval: Before Each Use
Refer to the engine operator's manual for dipstick and oil fill
locations and specific engine oil check and fill procedures.
Changing the Engine Oil and Filter
1. Warm the engine by running it for a few minutes.
(Refer to the engine operator's manual for oil and filter
replacement instructions.)
2. Remove the oil drain hose (A, Figure 20) from its storage
position and route the hose so that when the oil drain
cap (B) is removed the oil can be drained into a suitable
container (C).
20
3. Place a suitable container under the oil drain hose to
catch the oil. Turn and remove the oil drain cap and drain
the engine oil.
4. After draining, install the cap and wipe up any spilled oil.
Install the oil drain hose to its storage position so it is
retained during normal operation.
5. Place an absorbent shop cloth under the engine oil filter
(D). Remove the engine oil filter and replace with a new
one.
6. Add engine oil (refer to engine operator’s manual) in the
fill tube (E) and check the amount of oil in the engine
using the engine oil dipstick (F).
7. Remove the shop cloth and wipe up any spilled oil.
Clean the Engine Compartment with Air
and Water
Pressurized air and/or water can cause debris and/or hot
water to be blown out. This action could result in personal
injury.
When cleaning with air and/or water wear protective clothing,
protective shoes, and eye protection. Eye protection includes
goggles or a protective face shield.
26 stihlusa.com
The maximum air pressure for cleaning purposes must be
below 205 kPa (30 psi). The maximum water pressure for
cleaning purposes must be below 275 kPa (40 psi).
Engine Maintenance
For engine maintenance schedules and procedures, please
refer to the engine operator's manual.
Containing Spilled Fluids and Proper
Disposal of Waste
Make sure that fluids are contained when performing
inspection, maintenance, testing, adjustment, and repair
of the unit. Be prepared to collect the fluid with suitable
leakproof containers before opening or disassembling any
component containing fluids. Do not pour waste onto the
ground, down a drain, or into any source of water.
Improper disposal of waste can threaten the environment.
Dispose of all fluids according to local regulations and
mandates.
Servicing the Exhaust System
Inspect the muffler for cracks, corrosion, or other damage.
Remove the spark arrester, if equipped, and inspect
for damage or carbon blockage. If replacement parts
are required, make sure to use only original equipment
replacement parts.
WARNING
Replacement parts must be of the same design and
installed in the same position as the original parts. Other
parts could result in damage or an injury.
Replacing the Spark Arrester:
CAUTION
Wait until the muffler is cool before working around or near
the muffler.
1. Loosen the set screw (A, Figure 21) on the retaining ring
(B) and slide off over the tip of the tailpipe extension (C).
21
2. Remove the tailpipe extension. You may need to use
pliers to remove the tailpipe extension if it is stuck due to
corrosion.
3. Slide the screen (D) out of the tailpipe (E) and shake
the screen to remove the built up soot and carbon. The
amount of carbon collected will vary depending on the
fuel used, air quality, engine age, and condition. (A soft
non-metallic brush may be required to fully clean the
screen).
4. Carefully inspect the screen for any tears, rips or any
other damage which will prevent the screen from
operating properly. Replace screen if damaged.
5. Slide the screen into the tailpipe of the muffler until the
retaining lip (F) is sitting against the tip of the tailpipe.
6. Slide the tailpipe extension over the tailpipe of the muffler.
The extension is designed to fit tightly and you may need
to twist it to get it to slide on.
7. Slide the retaining ring over the tailpipe extension until it
circles the expanded section of the extension where the
muffler tailpipe and tailpipe extension overlap. Torque set
screw to 38 in-lbs (4,3 Nm).
Fuse Identification and Location
The electrical system for this unit is equipped with
replaceable fuse(s). See the chart below for the circuit,
amperage, and approximate location of the fuses.
Non-suspension Models:
Circuit Amperage Approximate Location
Main 20 amp Center of the unit and
near the battery.
Suspension Models:
Circuit Amperage Approximate Location
Main 20 amp Center of the unit and
near the battery.
USB Charging Port 5 amp Center of the unit and
near the battery.
Servicing the Hydraulic System
Non-Suspension Models:
27
Units without a suspension system are equipped with two
(2) sealed transmissions. If your transmission requires any
service work please see your authorized STIHL servicing
dealer to have this work performed.
Suspension Models:
Units with a suspension system are equipped with two (2)
transmissions and oil expansion tanks. Each transmission
has its own expansion tank. Please follow the instructions in
the following sections for the service and maintenance for
your unit’s transmissions.
Check / Fill Transmission Oil Level
This unit is equipped with two transmission oil tanks. One
transmission oil tank only supplies oil to one transmission.
The level of oil in both transmission oil tanks must be
checked, and if necessary, filled.
Oil Type: 20W-50 conventional detergent motor oil.
1. Locate the transmission oil tanks (A, Figure 22).
22
2. Check the oil level when the unit is cold. The oil should be
up to the "FULL COLD" mark (B). If the oil is below this
level, proceed to step #3.
3. Before removing the tank caps (C), make sure the area
around the tank cap and fill neck of the tank is free of
dust, dirt, or other debris. Remove the tank cap.
4. Add oil up to the "FULL COLD" mark.
5. Reinstall the tank caps.
6. After adding oil to the tanks, it may be necessary to purge
air from the hydraulic system. See Purging the Air from
the Hydraulic System procedure. If the unit is not driving
properly, see your authorized STIHL servicing dealer.
Transmission Oil Filter Change
Change Interval: Every 400 Hours or Yearly (Initial hydraulic
oil and filter change after first 100 hours of operation).
It is recommended that the procedure for changing the
hydraulic oil and transmission filter be performed by an
authorized STIHL servicing dealer.
Purging the Air from the Hydraulic System
Due to the effects air has on efficiency in hydraulic drive
systems, it is critical that it be purged from the system.
These purge procedures should be implemented any time a
hydraulic system has been opened to facilitate maintenance
or any additional oil has been added to the system.
The resulting symptoms of air in the hydraulic system may be:
• Noisy operation.
• Lack of power or drive after short term operation.
• High operation temperature and excessive expansion of
oil.
Before starting, make sure the transaxles/transmissions are
at the proper oil levels. If it is not, fill to the specifications
outlined in the Check / Fill Transmission Oil Level procedure.
Purging Air from the Hydraulic System:
1. Chock the front wheels to prevent the unit from rolling.
Raise the rear of the unit so that the unit's rear tires do
not contact the ground. Position jack stands under the
rear bumper of the unit to secure it.
2. Open the transaxle’s bypass valves (see Pushing the
Unit by Hand for the location and function of the bypass
valves), start the engine, release the parking brake, and
slowly move the unit’s ground speed control levers in both
forward and reverse directions (5 to 6 times), as air is
purged from the unit, the oil level will drop.
3. Stop the engine and engage the parking brake.
4. Close the transaxle’s bypass valves, start the engine,
release the parking brake, and slowly move the unit’s
ground speed control levers in both forward and reverse
directions (5 to 6 times), as air is purged from the unit, the
oil level will drop.
5. Stop the engine. Remove the jack stands from
underneath the unit.
6. Repeat the process detailed above but with the unit's
drive wheels on the ground. The procedure should be
performed in an area free of any objects or bystanders.
It may be necessary to repeat the process detailed above
until all the air is completely purged from the system. When
the transaxles/transmissions operate at normal noise levels
and move smoothly forward and reverse at normal speeds,
then the transaxles/transmissions are considered purged.
Lubrication
Lubricate the unit at the location shown in the following
figures as well as the lubrication points listed below.
28 stihlusa.com
Grease:
• Mower deck spindles (A, Figure 23).
• Rear transmission cradle pivots (A, Figure 24
-Suspension models only).
• Front caster wheel axles (A, Figure 25).
Use grease fittings when present. Disassemble parts to apply
grease to moving parts when grease fittings are not installed.
Not all greases are compatible. Your product is manufactured
using Heavy Duty Lithium Complex EP, NLGI grade 2
grease.Using non-compatible grease could damage or cause
premature parts failures.
Oil:
• Deck lift linkage pivots (A, Figures 26 and 27).
• Mower deck idler arm (B, Figures 26 and 27).
Generally, all moving metal parts should be oiled where
contact is made with other parts. Keep oil and grease off belts
and pulleys. Remember to wipe fittings and surfaces clean
both before and after lubrication.
23
24
25
26
27
Servicing the Mower Blades
29
Removing the Mower Blades
CAUTION
Laceration hazard
Mower blades are sharp.
Always wear gloves when handling, or working near, mower
blades.
1. Use a block of wood to prevent the mower blade from
turning as shown in Figure 28.
28
2. Using a wrench, remove the bolt securing the blade to the
spindle.
Inspecting, Sharpening, and Balancing the
Mower Blades
CAUTION
Laceration hazard.
Mower blades are sharp.
Always wear gloves when handling, or working near, mower
blades.
1. Remove the mower blade from the unit. See Removing
the Mower Blades.
2. Clean the blade to remove any dried grass or other
debris.
DANGER
Thrown objects hazard
Avoid injury: a worn or damaged mower blade can break
and a piece of the blade could be thrown into the operator's
area or bystander's area resulting in serious personal injury
or death.
• Inspect the mower blade every 25 hours or at least
once per year.
• If the mower blade hits a solid object, stop the engine
immediately and inspect the mower blades.
• Never weld or straighten bent mower blades.
3. Inspect the mower blade (Figure 29). Discard the mower
blade if it has any of the following conditions:
• More than .5" (12,7 mm) of the mower blade metal
has been removed from previous sharpening or wear
(A).
• The air lifts are excessively eroded (B) and the notch
(C) is .25" (6,35 mm) deep or greater.
• The mower blade is broken or bent.
29
4. If the cutting edges are not sharp or have nicks, sharpen
the blades.
WARNING
Thrown objects and fire hazard
Grinding mower blades throws sparks and fine metal
particles that are capable of igniting gasoline and gasoline
vapors, and that can injure unprotected eyes.
Be sure all flammable materials are cleared from the area
where grinding will occur.
Always wear safety glasses or goggles when grinding
mower blades.
30 stihlusa.com
5. Use a grinder, hand file, or electric blade sharpener to
sharpen the mower bladesby removing an equal amount
of material from the cutting edge of each end of the blade.
6. Keep the original bevel (A, Figure 30) when grinding. DO
NOT change the mower blade bevel.
30
7. The mower blade should have a maximum of 1/64" (0,40
mm) cutting edge (B) or less.
CAUTION
Thrown objects hazard.
An unbalanced mower blade can create excessive vibration
and damage the unit, or cause mower blade failure resulting
in thrown debris.
Be sure blade is balanced before installing.
8. Clamp a nail in a bench vise, hang the blade on the nail,
and position the blade in a level horizontal position as
shown in Figure 31.
31
9. Check the balance of the blade. If either end of the
blade moves downward the end that moves downward
is heavier than the other. Sharpen the heavy end until
balance is achieved.
10. Repeat the process until the mower blade remains in the
horizontal, level position.
Installing Mower Blades
CAUTION
Laceration hazard
Mower blades are sharp.
Always wear gloves when handling, or working near, mower
blades.
1. Install each blade with the airlifts (A, Figure 32) pointing
up towards the mower deck as shown. Install the concave
side of the washer (B) towards the blade. Install the blade
mounting bolt (C) hand tight to hold the washer and blade
onto the shaft (make sure the blade is fully seated onto
the shaft).
32
2. Tighten the blade mounting bolt to 50 - 60 ft. lbs. (68 - 81
Nm) of torque while holding onto the pulley bolt (D) with a
wrench.
3. Tighten the pulley bolt to 50 - 60 ft. lbs. (68 - 81 Nm) of
torque while holding onto the blade mounting bolt with a
wrench.
Seat And Ground Speed Control Lever
Adjustments
The seat and ground speed control levers should be adjusted
so that the ground speed control levers can be moved
through their full range of motion without contacting the
operator’s legs.
Seat Adjustment
1. Raise the seat.
2. Loosen the adjustment hardware (A or B, Figure33,
depending on seat type) under the seat base.
3. Slide the seat forward or backward to the desired
position.
4. Tighten the hardware to 80 lb-in (9 Nm).
31
33
Ground Speed Control Lever Adjustment
1. Loosen the ground speed control lever mounting
hardware (A, Figure34)to adjust the levers forward and
backward.
2. Remove the hardware to raise or lower the levers.
3. Always be sure to adjust both levers so that they are
aligned (B, Figure34).
4. After adjustment is complete, tighten the hardware to 13
lb-ft (18 Nm).
34
Speed Balancing (Tracking) Adjustment
If the unit drifts to the right or left when the ground speed
control levers are in the maximum forward position, the top
speed of each of these control levers can be balanced. Only
adjust the speed of the wheel that is traveling faster.
1. Tighten the knob (A, Figure 35)of the faster wheel by 1/2-
turn (clockwise) increments until the unit travels (tracks)
straight.
WARNING
DO NOT adjust the unit for a faster overall speed forward or
reverse than it was designed.
35
Checking Tire Pressures
Tire pressure should be checked periodically (see Figure
36), and maintained at the levels shown in the Specifications
chart. Note that these pressures may differ slightly from the
"Max Inflation" stamped on the side-wall of the tires. The
pressures shown provide proper traction and extend tire life.
36
Cutting Height Adjustment
The deck lift pedal adjusts the mower cutting height. The
cutting height is adjustable between 1-1/2" (3,8 cm) and
4-1/2" (11,4 cm) in 1/4" (0,64 cm) increments.
To adjust cutting height:
32 stihlusa.com
1. Fully depress the deck lift pedal (A, Figure 37) until the
deck lift lock lever (B) locks the deck into the highest
position (transport position).
37
2. Place the cutting height adjustment pin (C) into the hole
for the desired cutting height.
Note:Make sure the pin is inserted into the holes in both
upper and lower plates of the adjustment bracket (D).
3. Depress the deck lift foot pedal and then push the deck
lift lock lever towards the right to release the lock.
4. Slowly release the deck lift pedal until it comes to rest
against the cutting height adjustment pin.
Floor Pan Removal and Installation
This unit is equipped with a removable floor pan which can be
removed to provide better access to the mower deck.
1. Loosen and remove the retaining hardware (A, Figure 38)
that secures the floor pan (B) to the frame of the unit.
38
2. Tilt the back end of the floor pan up and then remove it
from the unit.
3. To install the floor pan: reverse the removal procedure.
Neutral Adjustment
The neutral system for this unit is a function of the transaxles.
1. Drive the unit to a flat, level surface. Engage the parking
brake and disengage the PTO.
2. Without touching the ground speed control levers
disengage the parking brake. If the unit moves, the
neutral systems on the transaxles are not correctly
adjusted. See your authorized STIHL servicing dealer.
Suspension Adjustment (if equipped)
The shock assemblies (A, Figure 39 - front shown, rear
similar) can be adjusted to vary the amount of pre-load
applied to the springs. This allows the operator to customize
the ride according to operator’s weight and operating
conditions.
Less Pre-Load:
• Light operator weight
• Softer, more cushioned ride
• Best for relatively flat terrain
More Pre-Load:
• Heavy operator weight
• Stiffer, more rigid ride
• Better handling and greater stability on hilly terrain
To Adjust the Spring Pre-Load:
1. Park the unit on a flat, level surface. Disengage the PTO,
pivot the ground speed control levers out to the START/
PARK position, and stop the engine.
2. Turn the pre-load adjustment collar (B, Figure 39) to a
higher notch (-) to decrease the pre-load, or to a lower
notch (+) to increase the pre-load. Make sure all shocks
are set to the same amount of pre-load.
33
39
Parking Brake Adjustment
The parking brake is not adjustable. If the parking brake
does not function properly, do not use the zero-turn riding
mower! See your authorized STIHL servicing dealer to have
the parking brake serviced.
Mower Deck Removal and Installation
Removing the mower deck makes deck maintenance items
easier to perform.
1. Drive the unit to a flat, level surface and return the ground
speed control levers to the middle (NEUTRAL) position
to stop the unit's movement. Pivot the levers outward
to lock them in the START/PARK position. This action
automatically engages the parking brake.
2. Disengage the PTO by pushing down on the PTO
switch.Move the throttle control to the SLOW position
and turn the ignition switch to OFF. Remove the key.
3. Remove the mower deck drive belt as described in
Mower Deck Drive Belt Replacement.
4. Lower the mower deck to its lowest cutting height.
5. Using a board or with the help of a second person,
lift the front of the deck to relieve the pressure on the
mounting hardware. Remove the pin (A, Figure 40) and
clip (B).Carefully lower the deck to the ground.
40
6. Using a board or with the help of a second person, lift
the left rear of the deck to relieve the pressure on the
mounting hardware. Remove the washer (C) and clip
(D).Carefully lower the deck to the ground. Repeat to
disconnect the right side of the deck.
7. Raise the deck to its highest cutting position and then
slide the mower deck out from beneath the left side of the
unit.
8. Reverse the process to install the mower deck.
9. Check the mower deck leveling as described in Deck
Leveling Adjustment.
Deck Leveling Adjustment
WARNING
Wear heavy gloves when handling or working around
cutting blades. Blades are extremely sharp and can cause
severe injury.
1. Drive the unit to a flat, level surface and return the ground
speed control levers to the middle (NEUTRAL) position
to stop the unit's movement. Pivot the levers outward
to lock them in the START/PARK position. This action
automatically engages the parking brake.
2. Disengage the PTO by pushing down on the PTO
switch.Move the throttle control to the SLOW position
and turn the ignition switch to OFF. Remove the key.
3. Set the mower deck to the 4-1/2" (11,4 cm) cutting height.
4. Turn the front caster wheels so they are facing front-to-
back.
34 stihlusa.com
5. Verify that the tire pressures are correct:
• Front: 22 psi (1,52 bar)
• Rear: 12 psi (0,83 bar)
6. Verify that the mower blades are flat, and not bent or
broken. A bent or broken blade must be replaced.
7. Position the two mower blades so that they are side-to-
side.
8. Measure the distance between the outside tips of the
blades and the ground (A and B, Figure 41).
41
• if measurements A and B DO NOT measure
4-1/2" (11,4 cm), adjustment is needed. Continue with
step # 9.
• if measurements A and B DO measure 4-1/2" (11,4
cm) no adjustment is needed, skip forward to step #
10.
9. Tighten the nuts (A, Figure 42) (right or left side) as
needed to adjust side-to-side leveling.The difference
between measurements should be less than 1/8" (3 mm).
42
10.
• 42" Mower Decks: Position the right side blade so it
is pointing front-to-back.
• 52" Mower Decks: Position the right side and center
blades so they point front-to-back.
11. Measure the distance between the outside tips of the
blades and the ground (A and B, Figure 43).
35
43
• 42" Mower Decks: The difference between
measurement A and B should be less than 1/8" (3
mm).
• 52" Mower Decks: The rear measurement A should
be 3/16" (5 mm) higher than the front measurement
B.
12. If adjustment is necessary, turn the front adjustment nut
(A, Figure 44) clockwise (B) to raise the front of the deck
or counter-clockwise (C) to lower the front of the deck.
44
Mower Deck Drive Belt Replacement
NOTICE
To avoid damaging belt, do not pry over pulleys.
1. Drive the unit to a flat, level surface and return the ground
speed control levers to the middle (NEUTRAL) position
to stop the unit's movement. Pivot the levers outward
to lock them in the START/PARK position. This action
automatically engages the parking brake.
2. Disengage the PTO by pushing down on the PTO
switch.Move the throttle control to the SLOW position
and turn the ignition switch to OFF. Remove the key.
3. Position the deck at the 2-1/2" (6,4 cm) cutting height.
4. Remove the floor pan and mower deck guards to gain
access to the mower deck drive belt.
WARNING
Use extreme caution when rotating the idler arm with your
hand due to the increased tension in the spring as the idler
arm is being rotated. Injury may result if the idler arm is
prematurely released while the spring is under tension.
5. Rotate the idler arm (A, Figures 45 and 46) in the
direction so that it stretches the belt tensioning spring (B)
to relieve the tension on the belt (C).
36 stihlusa.com
45
46
6.
• 42" Models: Remove the belt from the rear stationary
idler pulley (D, Figure 45). Carefully allow the idler
arm to rotate back into position.
• 52" Models: Remove the belt from the center spindle
pulley (D, Figure 46). Carefully allow the idler arm to
rotate back into position.
7. Remove the old belt and replace with a new one.
8.
• 42"Models: Make sure that the V-side of the belt is
installed in the grooves of the two (2) spindle pulleys
(E, Figure 45) and the PTO clutch pulley (F) and
that the back side of the belt contacts the face of the
adjustable idler pulley (G). Carefully rotate the idler
arm so that is stretches the tensioning spring and
install the mower deck so that the back side of the
belt contacts the rear stationary idler pulley (D).
• 52" Models: Make sure that the V-side of the belt is
installed in the grooves of the left and right spindle
pulleys (E, Figure 46) and the PTO clutch pulley (F)
and that the back side of the belt contacts the face
of the adjustable idler pulley (G) and the front and
rear stationary idler pulleys (H and I). Carefully rotate
the idler arm so that it stretches the tensioning spring
and install the mower deck drive belt so that V-side
of the belt goes into the grooves of the center spindle
pulley.
9. Carefully release the tension on the idler arm.
10. Install the mower deck guard and the floor pan.
11. Run the mower deck under a no-load condition for about
five (5) minutes to break in the new belt.
Washing the Mower Deck
The washout port allows you to connect a typical garden hose
to the left-hand side of the mower deck to remove grass and
debris from the underside.
WARNING
Amputation and Thrown Object Hazard.
Contact with the mower blades, or with objects thrown by
the mower blades, could result in death or serious injury.
• Before running the mower, make sure the hose is
properly connected and does not come into contact with
the blades.
• When the mower is running and the blades are
engaged, the person cleaning the mower deck must be
in the operator position, with no bystanders in the area.
1. Park the unit on a smooth level surface.
2. Attach the quick disconnect (C, Figure 47) to garden hose
(B) and connect to the washout port (A) on the mower
deck.
47
3. Run water to remove grass and debris from the underside
of the mower deck.
37
4. Turn the mower on and place in the highest cutting
position.
5. Turn the mower off.
6. Remove the garden hose and quick disconnect from the
washout port when completed.
Transmission Drive Belt Replacement
This zero-turn riding mower is equipped with a transmission
drive belt (A, Figure 48) that is located under the engine deck
of the unit.
48
Inspect the Condition of the Transmission Drive Belt
Service Interval: Every 400 hours or annually.
1. Drive the unit to a flat, level surface and return the ground
speed control levers to the middle (NEUTRAL) position
to stop the unit's movement. Pivot the levers outward
to lock them in the START/PARK position. This action
automatically engages the parking brake.
2. Disengage the PTO by pushing down on the PTO
switch.Move the throttle control to the SLOW position
and turn the ignition switch to OFF. Remove the key.
3. Visually inspect the belt (A, Figure 48) for cracks, frayed
edges, burn marks or any other damage. If the belt is
damaged, it must be replaced.
4. To replace the transmission drive belt the PTO clutch
must be removed from the engine's crankshaft so it
is recommended that the procedure for replacing the
transmission drive belt be performed by an authorized
STIHL servicing dealer.
Battery Maintenance
DANGER
Be careful when handling the battery.
Battery acid can cause severe burns. Avoid contact with
skin. Wear protective gear (safety goggles/face shield and
gloves) when working with the battery.
Keep the battery out of reach of children.
To avoid an explosion, keep open flames and sparks away
from the battery, especially while charging.
When removing or installing battery cables, disconnect the
negative cable FIRST and reconnect it LAST. If not done in
this order, the positive terminal can be shorted to the frame
by a tool.
Cleaning the Battery and Cables
This unit is equipped with a maintenance-free BCIU1 battery.
1. Disconnect the cables from the battery, negative [-] cable
first (A, Figure 49).
49
2. Clean the battery terminals and cable ends with a wire
brush until shiny.
3. Reinstall the battery and reattach the battery cables,
positive [+] cable first (B).
4. Coat the cable ends and the battery terminals with
petroleum jelly or non-conducting grease.
Checking Battery Voltage
A voltmeter can be used to determine condition of the battery.
When the engine is off, the voltmeter shows battery voltage,
which should be 12 volts. When the engine is running, the
voltmeter shows voltage of charging circuit which normally is
13 to 14 volts.
A dead battery, or one too weak to start the engine, may not
mean the battery needs to be replaced. For example, it may
mean that the alternator is not charging the battery properly.
38 stihlusa.com
If there is any doubt about the cause of the problem, see your
authorized STIHL servicing dealer. If you need to replace
the battery, follow the steps under Cleaning the Battery and
Cables.
Charging the Battery
WARNING
Keep open flames and sparks away from the battery; the
gasses coming from it are highly explosive. Ventilate the
battery well during charging.
A dead battery or one too weak to start the engine may be
the result of a defect in the charging system or other electrical
component. If there is any doubt about the cause of the
problem, see your authorized STIHL servicing dealer.
To charge the battery, follow the instructions provided by the
battery charger manufacturer as well as all warnings included
in the OPERATOR SAFETYsection of this manual. Charge
the battery until fully charged. Do not charge at a rate higher
than 10 amps.
Jump Starting with Auxiliary (Booster) Battery
Jump starting is not recommended.
39
Troubleshooting
While normal care and regular maintenance will extend the
life of your unit, prolonged or constant use may eventually
require that service be performed to allow it to continue to
operate properly.
This troubleshooting guide lists the most common problems,
their causes, and remedies.
Refer to MAINTENANCE PROCEDURESfor instructions on
how to perform most of these minor adjustments and service
repairs yourself. If you prefer, all of these procedures can be
performed for you by your authorized STIHL servicing dealer.
WARNING
Remove ignition key prior to performing maintenance on the
unit.
To avoid serious injury, perform maintenance on the unit
or mower deck only when the engine is stopped and the
parking brake is engaged.
Always remove the ignition key, disconnect the spark plug
wire(s) and fasten it away from the plug(s) before beginning
the maintenance, to prevent accidental starting of the
engine.
Troubleshooting the Zero-Turn Riding
Mower
Problem: Engine will not turn over and start.
Cause Remedy
Ground speed control levers are not
in START/PARK positions.
Lock ground speed control levers in
START/PARK positions.
PTO (electric clutch) switch is in ON
position.
Place in OFF position.
Out of fuel. If engine is hot, allow it to cool, then
refill the fuel tank.
Engine flooded. Open the choke (if equipped).
Battery terminals require cleaning. Clean the battery terminals.
Battery discharged or dead. Recharge or replace.
Spark plug(s) faulty, fouled or
incorrectly gapped.
Clean and gap or replace.
Engine starts hard or runs poorly.
Cause Remedy
Fuel mixture too rich. Clean air filter. Check the choke (if
equipped).
Spark plug faulty, fouled or
incorrectly gapped.
Clean and gap or replace.
Engine knocks.
Cause Remedy
Low oil level. Check/add oil as required.
Using wrong grade oil. See engine operator's manual.
Excessive oil consumption.
Cause Remedy
Excessive oil consumption.
Engine running too hot. Check engine fins, blower screen,
and air cleaner.
Using wrong grade oil. See engine operator's manual.
Too much oil in crankcase. Drain excess oil.
Engine exhaust is black.
Cause Remedy
Dirty air filter. Replace air filter.
Engine choke control is in closed
position.
Open choke control (if equipped).
Engine runs, but unit will not drive or handles poorly.
Cause Remedy
Transmission release lever(s) in
"bypass" position.
Move transmission release lever(s)
to the "drive" position.
Transmission drive belt or pulleys is
greasy or oily.
Clean as required.
Steering lever linkages are loose. See an authorized STIHL servicing
dealer.
For all other issues, see an authorized STIHL servicing
dealer.
Troubleshooting Common Cutting
Problems
Problem: Streaking
Streaking is when thin strips of uncut grass are left behind the mower.
Streaking is usually caused by operator error or poor blade maintenance.
Cause Remedy
Blades are not sharp. Sharpen your blades.
Blades are worn down too far. Replace your blades.
Engine speed is too slow. Always mow at full throttle.
Ground speed is too fast. Slow down.
Deck is plugged with grass. Clean out the mower.
Not overlapping cutting rows enough. Overlap your cutting rows
Not overlapping enough when
turning.
When turning your effective cutting
width decreases–overlap more when
turning.
Problem: Scalping
Scalping is when the mower deck comes close to or hits the ground.
Scalping can be caused by the mower deck misadjustment, unevenness in
the lawn, or by mower deck bouncing because the ground speed is too fast.
Cause Remedy
Lawn is uneven or bumpy. Roll or level the lawn.
Mower deck cutting height is set too
low.
Raise the cutting height.
Ground speed is too fast. Slow down.
40 stihlusa.com
Problem: Scalping
Deck is not leveled correctly. Correctly level the deck.
Tire pressure is low or uneven. Check and inflate the tires.
Problem: Stepped Cutting
Stepped cutting is sharp ridges or uneven levels left in the lawn
surface. Stepped cutting is usually caused by mower deck damage or
misadjustment, or damage to the mower blades.
Cause Remedy
Deck is not leveled correctly. Level the deck correctly.
Tires are not properly inflated. Check and inflate the tires.
Blades are damaged. Replace the blades.
Deck shell is damaged. Repair or replace the deck.
Mower spindle is bent or loose. Repair or replace the spindle.
Blades are installed incorrectly. Reinstall the blades correctly.
Problem: Uneven Cutting
Uneven cutting is waviness or smooth troughs in the lawn surface. Uneven
cutting is usually caused by mower deck damage or misadjustment.
Cause Remedy
Deck is not leveled correctly. Level the deck correctly.
Blades are dull or worn. Sharpen or replace the blades.
Blades are damaged. Replace the blades.
Deck is clogged with grass clippings. Clean out the deck.
Deck shell is damaged. Repair or replace the deck.
Mower spindle is bent or loose. Repair or replace the spindle.
Blades are installed incorrectly. Reinstall the blades correctly.
Tires are not properly inflated. Check and inflate the tires.
Problem: Stringers
Stringers are sparse patches of uncut grass left behind the mower.
Stringers are usually caused by operator error or poor blade maintenance.
Cause Remedy
Blades are not sharp or nicked. Sharpen your blades.
Blades are worn down too far. Replace your blades.
Engine speed is too slow. Always mow at full throttle.
Ground speed is too fast. Slow down.
Deck is plugged with grass. Clean out the mower.
41
Specifications
Specifications are correct at time of printing and are subject to
change without notice.
ENGINE
For complete engine specifications see the engine
manufacturer's operator's manual included with your unit.
Fits models: RZ 142.0
Briggs & Stratton® 44U777
Professional Series with ReadyStart®
Make Briggs & Stratton®
Model 44U777-0010-G1
Electrical System 12 volt, 9 amp alternator: Battery:
230 CCA
Fits models: RZ 152.0
Briggs & Stratton® 44S977
Professional Series with ReadyStart®
Make Briggs & Stratton®
Model 44S977-0046-G1
Electrical System 12 volt, 9 amp alternator; Battery:
230 CCA
CHASSIS
Fuel Tank Capacity 3 gallons (11,4 L)
Rear Wheels
Tire Size (Non-suspension Models) 20 X 8 - 8
Tire Size (Suspension Models) 20 X 10 - 10
Inflation Pressure 12 psi (0,83 bar)
Front Tires
Tire Size 11 X 6 - 5
Inflation Pressure 22 psi (1,52 bar)
TRANSMISSIONS
Non-suspension Models:
Make Hydro-Gear®
LH Model ZD-AUBB-2A7B-3XPX
RH Model ZD-DUBB-2A7C-2XPX
Type EZT®
Hydraulic Fluid Sealed Transaxle
Forward: 0 - 7 mph (0 - 11 km/h)Speeds @ 3400 rpm
Reverse: 0 - 4 mph (0 - 6 km/h)
Suspension Models:
Make Hydro-Gear®
LH Model ZH-JPBB-SF7B-2XLX
RH Model ZH-MPBB-SF7C-3XLX
Type ZT-2800®
Hydraulic Fluid SAE 20W-50 motor oil
Forward: 0 - 8 mph (0 - 13 km/h)Speeds @ 3400 rpm
Reverse: 0 - 4 mph (0 - 6 km/h)
DIMENSIONS
Models with 42" Mower Decks
Overall Length 74" (188 cm)
Overall Width 48" (122 cm)
Overall Height 40" (102 cm)
Models with 52" Mower Decks
Overall Length 74" (188 cm)
Overall Width 54" (137 cm)
Overall Height 41" (104 cm)
42 stihlusa.com
Limited Warranty
STIHL Incorporated Limited Warranty Policy
This product is sold subject to the STIHL Incorporated Limited Warranty Policy, available at www.stihlusa.com/warranty.html. It
can also be obtained from your authorized STIHL servicing dealer or by calling 1-800-GO-STIHL (1-800-467-8445).
If your unit is equipped with a dual function hour meter that displays both engine hours and PTO hours, warranty coverage is
based on the engine hours as displayed by the hour meter.
Notes
