This technical manual is written for an experienced
technician and contains sections that are specifically for
this product. It is a part of a total product support
program.
The manual is organized so that all the information on a
particular system is kept together. The order of grouping
is as follows:
INTRODUCTION
Safety
Specifications and
Information
• Table of Contents
• Specifications
• Component Location
• System Schematic
• Theory of Operation
• Troubleshooting Chart
• Diagnostics
• Tests & Adjustments
• Repair
Note: Depending on the particular section or system
being covered, not all of the above groups may be
used.
Each section will be identified with a symbol rather than a
number. The groups and pages within a section will be
consecutively numbered.
Engine – 20, 23 & 25 HP
Electrical System
Hydrostatic Power Train
Steering
We appreciate your input on this manual. If you find any
errors, or want to comment on the layout of the manual,
please mail your comments back to us.
This is the safety-alert symbol. When you see this
symbol on your machine or in this manual, be alert to
the potential for personal injury.
Follow recommended precautions and safe servicing
practices.
Understand Signal Words
A signal word—DANGER, WARNING, or CAUTION—
is used with the safety-alert symbol. DANGER
identifies the most serious hazards.
HANDLE FLUIDS SAFELY-AVOID
FIRES
Be Prepared For Emergencies
DANGER or WARNING safety signs are located near
specific hazards. General precautions are listed on
CAUTION safety signs. CAUTION also calls attention
to safety messages in this manual.
REPLACE SAFETY SIGNS
Replace missing or damaged safety signs. See the
machine operator’s manual for correct safety sign
placement.
When you work around fuel, do not smoke or work near
heaters or other fire hazards.
Store flammable fluids away from fire hazards. Do not
incinerate or puncture pressurized containers.
Make sure machine is clean of trash, grease, and
debris.
Do not store oily rags; they can ignite and burn
spontaneously.
Be prepared if a fire starts.
Keep a first aid kit and fire extinguisher handy.
Keep emergency numbers for doctors, ambulance
service, hospital, and fire department near your
telephone.
1 - 2
2/24/00
Page 4
SAFETY
USE CARE IN HANDLING AND
SER VICING BATTERIES
Prevent Battery Explosions
• Keep sparks, lighted matches, and open flame
away from the top of battery. Battery gas can
explode.
• Never check battery charge by placing a metal
object across the posts. Use a volt-meter or
hydrometer.
• Do not charge a frozen battery; it may explode.
Warm battery to 16°C (60°F).
Prevent Acid Burns
• Sulfuric acid in battery electrolyte is poisonous. It is
strong enough to burn skin, eat holes in clothing,
and cause blindness if splashed into eyes.
USE SAFE SERVICE PROCEDURES
Wear Protective Clothing
Wear close fitting clothing and safety equipment
appropriate to the job.
Prolonged exposure to loud noise can cause
impairment or loss of hearing. Wear a suitable hearing
protective device such as earmuffs or earplugs to
protect against objectionable or uncomfortable loud
noises.
Operating equipment safely requires the full attention
of the operator. Do not wear radio or music
headphones while operating machine.
Service Machines Safely
• Avoid acid burns by:
1. Filling batteries in a well-ventilated area.
2. Wearing eye protection and rubber gloves.
3. Av oiding breathing fumes when electrolyte is
added.
4. Avoiding spilling or dripping electrolyte.
5. Use proper jump start procedure.
• If you spill acid on yourself:
1. Flush your skin with water.
2. Apply baking soda or lime to help neutralize the
acid.
3. Flush your eyes with water for 10_15 minutes.
4. Get medical attention immediately.
• If acid is swallowed:
1. Drink large amounts of water or milk.
2. Then drink milk of magnesia, beaten eggs, or
vegetable oil.
3. Get medical attention immediately.
Tie long hair behind your head. Do not wear a necktie,
scarf, loose clothing, or necklace when you work near
machine tools or moving parts. If these items were to
get caught, severe injury could result.
Remove rings and other jewelry to prevent electrical
shorts and entanglement in moving parts.
Use Proper Tools
Use tools appropriate to the work. Makeshift tools and
procedures can create safety hazards. Use pow er tools
only to loosen threaded parts and fasteners. For
loosening and tightening hardware, use the correct size
tools.
DO NOT
fasteners. Avoid bodily injury caused by slipping
wrenches. Use only service parts meeting Jo hn Deere
specifications.
use U.S. measurement tools on metric
2/24/00
1 - 3
Page 5
SAFETY
Park Machine Safely
Before working on the machine:
1. Lower all equipment to the ground.
2. Stop the engine and remove the key.
3. Disconnect the battery ground strap.
4. Hang a “DO NOT OPERATE” tag in operator
station.
Support Machine Properly And Use
Proper Lifting Equipment
Using High Pressure Washers
Directing pressurized water at electronic/electrical
components or connectors, bearings, hydraulic seals,
fuel injection pumps or other sensitive parts and
components may cause product malfunctions. Reduce
pressure and spray at a 45 to 90 degree angle.
Illuminate Work Area Safely
Illuminate your work area adequately but safely. Use a
portable safety light for working inside or under the
machine. Make sure the bulb is enclosed by a wire
cage. The hot filament of an accidentally broken bulb
can ignite spilled fuel or oil.
Work In Ventilated Area
If you must work on a lifted machine or attachment,
securely support the machine or attachment.
Do not support the machine on cinder blocks, hollow
tiles, or props that may crumble under continuous load.
Do not work under a machine that is supported solely
by a jack. Follow recommended procedures in this
manual.
Lifting heavy components incorrectly can cause severe
injury or machine damage. Follow recommended
procedure for removal and installation of components
in the manual.
Work In Clean Area
Before starting a job:
1. Clean work area and machine.
2. Make sure you have all necessary tools to do your
job.
3. Have the right parts on hand.
4. Read all instructions thoroughly; do not attempt
shortcuts.
Engine exhaust fumes can cause sickness or death. If
it is necessary to run an engine in a n enclosed area,
remove the exhaust fumes from the area with an
exhaust pipe extension.
If you do not have an exhaust pipe extension, open the
doors and get outside air into the area.
WARNING: California Proposition 65
Warning:
Diesel engine exhaust and some of its constituents are
known to the State of California to cause cancer, birth
defects, and other reproductive harm.
Gasoline engine exhaust from this product contains
chemicals known to the State of California to cause
cancer, birth defects, or other reproductive harm.
Remove Paint Before Welding Or
Heating
Avoid potentially toxic fumes and dust. Hazardous
fumes can be generated when paint is heated by
welding, soldering, or using a torch. Do all work outside
or in a well ventilated area. Dispose of paint and
solvent properly. Remove paint before welding or
heating: If you sand or grind paint, avoid breathing the
dust. Wear an approved respir ator. If you use solvent or
paint stripper, remove stripper with soap and water
before welding. Remove solvent or paint stripper
containers and other flammable material from area.
Allow fumes to disperse at least 15 minutes before
welding or heating.
1 - 4
2/24/00
Page 6
SAFETY
Avoid Harmful Asbestos Dust
Avoid breathing dust that may be generated when
handling components containing asbestos fibers.
Inhaled asbestos fibers may cause lung cancer.
Components in products that may contain asbestos
fibers are brake pads, brake band and lining
assemblies, clutch plates, and some gaskets. The
asbestos used in these components is usually found in
a resin or sealed in some way. Nor mal handling is not
hazardous as long as airborne dust containing
asbestos is not generated.
Avoid creating dust. Never use compressed air for
cleaning. Avoid brushing or grinding material
containing asbestos. When servicing, wear an
approved respirator. A special vacuum cleaner is
recommended to clean asbestos. If not available, apply
a mist of oil or water on the material containing
asbestos. Keep bystanders away from the area.
SERVICE TIRES SAFELY
AVOID INJURY FROM ROTATING
BLADES, AUGERS AND PTO
SHAFTS
Keep hands and feet away while machine is running.
Shut off power to service, lubricate or remove mower
blades, augers or PTO shafts.
HANDLE CHEMICAL PRODUCTS
SAFELY
Explosive separation of a tire and rim parts can cause
serious injury or death.
Do not attempt to mount a tire unless you have the
proper equipment and experience to perform the job.
Always maintain the correct tire pressure. Do not inflate
the tires above the recommended pressure. Ne v er weld
or heat a wheel and tire assembly. The heat can cause
an increase in air pressure resulting in a tire explosion.
Welding can structurally weaken or deform the wheel.
When inflating tires, use a clip-on chuck and extension
hose long enough to allow you to stand to one side and
NOT in front of or over the tire assembly. Use a safety
cage if available.
Check wheels for low pressure, cuts, bubbles,
damaged rims or missing lug bolts and nuts.
Direct exposure to hazardous chemicals can cause
serious injury. Potentially hazardous chemicals used
with John Deere equipment include such items as
lubricants, coolants, paints, and adhesives.
A Material Safety Data Sheet (MSDS) provides specific
details on chemical products: physical and health
hazards, safety procedures, and emergency response
techniques. Check the MSDS before you start any job
using a hazardous chemical. That way you will know
exactly what the risks are and how to do the job safely.
Then follow procedures and recommended equipment.
Dispose of Waste Properly
Improperly disposing of waste can threaten the
environment and ecology. Potentially harmful waste
used with John Deere equipment include such items as
oil, fuel, coolant, brake fluid, filters, and batteries. Use
leakproof containers when draining fluids. Do not use
food or beverage containers that may mislead
someone into drinking from them. Do not pour waste
onto the ground, down a drain, or into any water
source. Inquire on the proper way to recycle or dispose
of waste from your local environmental or recycling
center, or from your John Deere dealer.
2/24/00
1 - 5
Page 7
SAFETY
LIVE WITH SAFETY
Before returning machine to customer, make sure
machine is functioning properly, especially the safety
systems. Install all guards and shields.
DO NOT use these values if a different torque value or tightening procedure is given for a specific application.
Torque values listed are for general use only. Check tightness of fasteners periodically.
Shear bolts are designed to fail under predetermined loads. Always replace shear bolts with identical grade.
Fasteners should be replaced with the same or higher grade. If higher grade fasteners are used, these should only
be tightened to the strength of the original.
Make sure fasteners threads are clean and that you properly start thread engagement. This will prevent them from
failing when tightening.
Tighten plastic insert or crimped steel-type lock nuts to approximately 50 percent of the dry torque shown in the
chart, applied to the nut, not to the bolt head.
Tighten toothed or serrated-type lock nuts to the full torque value.
a
“Lubricated” means coated with a lubricant such as engine oil, or fasteners with phosphate and oil coatings.
“Dry” means plain or zinc plated without any lubrication.
b
Grade 2 applies for hex cap screws (not hex bolts) up to 152 mm (6 in.) long. Grade 1 applies for hex cap screws over
152 mm (6 in.) long, and for all other types of bolts and screws of any length.
2 - 6
3/2/00
Page 14
SPECIFICATIONS & INFORMATION
METRIC TORQUE VALUES
METRIC TORQUE VALUES
Property
Class
and
Head
Markings
Property
Class
and
Nut
Markings
4.8
4.8
4.8
5
5
510
8.8
8.8
8.8
10
10
9.8
9.8
9.8
10.9
10.9
10.9
10
10
10
12.9
12.9
12
Class 4.8Class 8.8 or 9.8Class 10.9Class 12.9
LubricatedaDry
DO NOT use these values if a different torque value or
tightening procedure is given for a specific application.
Torque values listed are for general use only. Check
tightness of fasteners periodically.
Shear bolts are designed to fail under predetermined
loads. Always replace shear bolts with identical
property class.
Fasteners should be replaced with the same or higher
property class. If higher property class fasteners are
used, these should only be tightened to the strength of
the original.
Make sure fasteners threads are clean and that you
properly start thread engagement. This will prevent
them from failing when tightening.
Tighten plastic insert or crimped steel-type lock nuts to
approximately 50 percent of the dry torque shown in
the chart, applied to the nut, not to the bolt head.
Tighten toothed or serrated-type lock nuts to the full
torque value.
a
“Lubricated” means coated with a lubricant such as
engine oil, or fasteners with phosphate and oil coatings.
“Dry” means plain or zinc plated without any lubrication.
3/2/00
2 - 7
Page 15
GASOLINE SPECIFICATIONS
SPECIFICATIONS & INFORMATION
GASOLINE SPECIFICATIONS
CAUTION
Handle fuel with care, it is highly flammable. DO
NOT refuel machine:
• Indoors. Always fill fuel tank outdoors.
• While you smoke.
• When machine is near and open flame or
sparks.
• When engine is running. STOP engine.
• When engine is hot. Allow it to cool.
Help prevent fires:
• Fill fuel tank only to bottom of filler neck.
• Clean oil, grease and dirt from machine.
• Clean up spilled fuel immediately.
• Do not store machine with fuel in tank in a
building where fumes may reach an open
flame or spark.
To prevent fire and explosion caused by static
electric discharge while you fill tank:
• Use approved, non-metal fuel container.
• When using a funnel, MAKE SURE it is
PLASTIC.
• Av oid using a funnel which has a metal screen
or filter.
LUBRICANT SPECIFICATIONS
ENGINE OIL
Use oil viscosity based on the expected air temperature
range during the period between oil changes.
The following oil is preferred:
• 10W30
IMPORTANT: To avoid engine damage:
• DO NOT mix oil with gasoline
• Use only clean oil and fuel
• Use clean approved containers and funnels.
• Store oil and fuel in an area protected from dust,
moisture and other contamination.
Unleaded fuel is recommended because it burns
cleaner and leaves less unburned deposits in engine
combustion chamber. Regular unleaded gasoline with
an anti-knock index of 85 octane or higher may be
used. Use of gasohol is acceptable as long as the ethyl
alcohol blend does not exceed 11 percent. Do not use
gasoline that contains Methanol.
Fill fuel tank at end of each day's operation. Fill only to
bottom of filler neck
.
GASOLINE STORAGE
Keep fuel in a clean container in a protected area. Do
not use deicers to remove water from fuel. Do not
depend on fuel filters to remove water.
If possible, install a water separator at the storage tank
outlet.
IMPORTANT: Keep all dirt, scale, water or other
foreign material out of fuel.
If mower is stored for the winter, add gasoline storage
stabilizer to the fuel. Follow directions on can.
Other oils may be used if they meet one of the
following:
• API Service Classification SG
• API Service Classification SF
• CCMC Specification G4
Oils meeting Military Specification MIL-L-46167B may
be used as arctic oils.
ENGINE BREAK–IN OIL
IMPORTANT: ONLY use a quality break-in oil in
rebuilt or remanufactured engines for the first 5
hours (maximum) of operation. DO NOT use oils
with heavier viscosity weights than SAE 5W-30
or oils meeting specifications API SG, SH; or
oils meeting CCMC Specification G5. These oils
will not allow rebuilt or remanufactured engines
to break-in properly.
2 - 8
3/2/00
Page 16
SPECIFICATIONS & INFORMATION
LUBRICANT SPECIFICATIONS
HYDROSTATIC TRANSMISSION OIL
Use the appropriate oil viscosity based on these air
temperature ranges. Operating outside of these
recommended oil air temperature ranges may cause
premature hydrostatic transmission failure.
IMPORTANT: ONLY use a quality SAE 5W-30 (2048)
or 5W-50 SYNTHETIC (2554) engine oil in this
transmission. Mixing of two viscosity grade oils
is NOT RECOMMENED. DO NOT use BIO–HY–
®
GARD
The following oil is
• S2048 use 5W-30 or 10W-30
• S2554 use 5W-50 SYNTHETIC
Use only oils that meet the following specifications:
• API Service Classifications SG or higher.
• CCMC Specifications G4 or higher.
in this transmission.
RECOMMENDED:
GREASE
Use grease based on the expected air temperature
range during the service interval.
The following greases are preferred:
• MOLY HIGH TEMPERATURE EP GREASE
• HIGH TEMPERATURE EP GREASE
• MULTI-PURPOSE GREASE
SAE 10W-30
SAE 5W-30
AIR TEMPERATURE
John Deere Dealers:
the following publications to recommend the proper oil
for your customers:
• Module DX,ENOIL2 in JDS–G135;
• Section 530, Lubricants & Hydraulics, of the John
Deere Merchandise Sales Guide;
• Lubrication Sales Manual PI7032.
You may want to cross-reference
M58275
Other greases may be used if they meet one of the
following:
• SAE Multipurpose EP Grease with a maximum of
5% molybdenum disulfide.
• SAE Multipurpose EP Grease
Greases meeting Military Specification MIL-G-10924F
may be used as arctic grease.
ALTERNATIVE LUBRICANTS
Conditions in certain geographical areas outside the
United States and Canada may require different
lubricant recommendations than these printed in this
manual or the operator's manual. Consult with your
John Deere Dealer, or Sales Branch to obtain the
alternative lubricant recommendations.
3/2/00
2 - 9
Page 17
SERIAL NUMBER LOCATIONS
SPECIFICATIONS & INFORMATION
SYNTHETIC LUBRICANTS
Synthetic lubricants may be used in equipment if they
meet the applicable performance requirements
(industry classification and/or military specification) as
shown in this group.
The recommended temperature limits and service or oil
change intervals should be maintained as shown in the
operator’s manual.
Avoid mixing different brands, grades, or types of oil.
Oil manufacturers blend additive in their oils to meet
certain specifications and performance requirements.
Mixing different oils can interfere with the proper
functioning of these additives and degrade lubricant
performance.
OIL FILTERS
Filtration of oils is critical to proper lubrication. Always
change filters regularly.
Use filters meeting John Deere performance
specification.
LUBRICANT STORAGE
ENGINE SERIAL NUMBER
Engine ID
Number
20 HP Engine
M99840
This machine can operate at top efficiency only if clean
lubricants are used.
Use clean containers to handle all lubricants. Store
them in an area protected from dust, moisture, and
other contamination. Store drums on their sides.
SERIAL NUMBER LOCATIONS
When working on machines or components that are
covered by warranty, it is IMPORTANT that you include
the tractor identification number and
serial numbers on the warranty claim form.
The location of tractor identification number and
component serial numbers are shown below.