YAMAHA PZ50W, PZ50GTW, PZ50FXW, PZ50MW, PZ50VTW, PZ50MPW SERVICE MANUAL
SERVICE MANUAL
PZ50W
PZ50GTW
PZ50FXW
PZ50MW
PZ50VTW
PZ50MPW
LIT-12618-02-588GC-28197-10
NOTICE
This manual was written by the Yamaha Motor
Company primarily for use by Yamaha dealers and
their qualified mechanics. It is not possible to put an
entire mechanic’s education into one manual, so it
is assumed that persons using this book to perform
maintenance and repairs on Yamaha snowmobiles
have a basic understanding of the mechanical concepts and procedures inherent in snowmobile
repair. Without such knowledge, attempted repairs
or service to this model may render it unfit and/or
unsafe to use. Yamaha Motor Company, Ltd. is
continually striving to improve all models manufactured by Yamaha. Modifications and significant
changes in specifications or procedures will be forwarded to all authorized Yamaha dealers and will,
where applicable, appear in future editions of this
manual.
HOW TO USE THIS MANUAL
Particularly important information is distinguished in
this manual by the following notations:
The Safety Alert Symbol means ATTENTION! BE
ALERT! YOUR SAFETY IS INVOLVED!
WARNING
Failure to follow WARNING instructions could result
in severe injury or death to the snowmobile operator, a bystander, or a person inspecting or repairing
the snowmobile.
CAUTION:
A CAUTION indicates special precautions that
must be taken to avoid damage to the snowmobile.
NOTE:
A NOTE provides key information that can make
procedures easier or clearer.
1st Edition, July 2006
All rights reserved. Any reprinting or
unauthorized use without the written
permission of Yamaha Motor Corporation,
U.S.A. is expressly prohibited.
Printed in U.S.A.
P/N.LIT-12618-02-58
MANUAL FORMAT
All of the procedures in this manual are organized
in a sequential, step-by-step format. The information has been compiled to provide the mechanic
with an easy to read, handy reference that contains
comprehensive explanations of all inspection,
repair, assembly, and disassembly operations.
In this revised format, the condition of a faulty component will precede an arrow symbol and the
course of action required to correct the problem will
follow the symbol, e.g.,
• Bearings
Pitting/damage → Replace.
EXPLODED DIAGRAM
Each chapter provides exploded diagrams before
each disassembly section to facilitate correct disassembly and assembly procedures.
1 2
GEN
INFO
34
INSP
ADJ
POWR
CHAS
TR
56
ENG
78
COOL
ILLUSTRATED SYMBOLS
(Refer to the illustration)
Illustrated symbols 1 to 9 are designed as thumb
tabs to indicate the chapter’s number and content.
1 General information
2 Periodic inspection and adjustment
3 Chassis
4 Power train
5 Engine
6 Cooling system
7 Fuel injection system
8 Electrical
9 Specifications
–+
9
FI
ELEC
SPEC
0AB
T
.
R
.
CDE
FGH
LT
IJK
E
LMN
B
G
LS
5
M
M
Illustrated symbols 0 to F are used to identify the
specifications which appear.
0
Filling fluid
A Lubricant
B Tightening
C Wear limit, clearance
D Engine speed
E Special tool
FΩ, V, A
Illustrated symbols G to O in the exploded diagram
indicate grade of lubricant and location of lubrication point.
G Apply locking agent (LOCTITE
H Apply Yamabond No.5
I Apply engine oil
J Apply gear oil
K Apply molybdenum disulfide oil
L Apply wheel bearing grease
M Apply low-temperature lithium-soap base grease
N Apply molybdenum disulfide grease
O Use new one
GEAR MOTOR ......................................... 8-57
GEAR MOTOR RELAY 1.......................... 8-58
GEAR MOTOR RELAY 2.......................... 8-58
GEAR MOTOR RELAY 3.......................... 8-59
GEN
MACHINE IDENTIFICATION
GENERAL INFORMATION
MACHINE IDENTIFICATION
FRAME SERIAL NUMBER
The frame serial number 1 is located on the right-hand side of the frame
(just below the front of the seat).
ENGINE SERIAL NUMBER
The engine serial number 1 is located on the left-hand side of the crankcase.
NOTE:
Designs and specifications are subject to change without notice.
INFO
1-1
GEN
IMPORTANT INFORMATION
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL AND DISASSEMBLY
INFO
1. Remove all dirt, mud, dust, and foreign material before removal and
disassembly.
While cleaning, take care to protect the electrical parts, such as relays,
switches, motor, resistors, controllers, etc., from high pressure water
splashes.
2. Use proper tools and cleaning equipment.
Refer to “SPECIAL TOOLS”.
3. When disassembling the machine, keep mated parts together. This
includes gears, cylinders, pistons, and other parts that have been
“mated” through normal wear. Mated parts must be reused or replaced
as an assembly.
4. During disassembly of the machine, clean all parts and place them in
trays in the order of disassembly. This will speed up assembly time and
help ensure that all parts are reinstalled correctly.
1
5. Keep all parts away from any source of fire.
6. Be sure to keep to the tightening torque specifications. When tightening bolts, nuts, and screws, start with those that have larger diameters,
and proceed from the inside to the outside in a crisscross pattern.
ALL REPLACEMENT PARTS
We recommend using genuine Yamaha parts for all replacements. Use oil
and grease recommended by Yamaha for assembly and adjustments.
1-2
GEN
IMPORTANT INFORMATION
GASKETS, OIL SEALS, AND O-RINGS
1. All gaskets, seals, and O-rings should be replaced when an engine is
overhauled. All gasket surfaces, oil seal lips, and O-rings must be
cleaned.
2. Properly oil all mating parts and bearings during reassembly. Apply
grease to the oil seal lips.
LOCK WASHERS/PLATES AND COTTER PINS
All lock washers/plates 1 and cotter pins must be replaced if they are
removed. Lock tab(s) should be bent along the bolt or nut flat(s) after the
bolt or nut has been properly tightened.
INFO
BEARINGS AND OIL SEALS
Install the bearings 1 and oil seals 2 with their manufacturer’s marks or
numbers facing outwards. (In other words, the stamped letters must be on
the side exposed to view.) When installing oil seals, apply a light coating
of lightweight lithium base grease to the seal lips. Oil the bearings liberally
when installing.
CAUTION:
Do not use compressed air to spin the bearings dry. This causes
damage to the surface of the bearings.
CIRCLIPS
All circlips should be inspected carefully before reassembly. Always
replace piston pin clips after one use. Replace misshapen circlips. When
installing a circlip 1, make sure that the sharp edged corner 2 is positioned opposite to the thrust 3 it receives. See the sectional view.
Shaft
4
LOCTITE
After installing fasteners that have LOCTITE® applied, wait 24 hours
before using the machine. This will give the LOCTITE
erly.
®
®
time to dry prop-
1-3
GEN
SPECIAL TOOLS
SPECIAL TOOLS
Some special tools are necessary for a completely accurate tune-up and
assembly. Using the correct special tool will help prevent damage that can
be caused by the use of improper tools or improvised techniques.
NOTE:
• Be sure to use the correct part number when ordering the tool, since the
part number may differ according to country.
• For USA and Canada, use part number starting with “YB-”, “YM-”, “YU-”
or “YS-”.
• For others, use part number starting with “90890-”.
FOR TUNE UP
• Dial gauge
P/N: YU-03097
90890-03097
This gauge is used for run out measurement.
INFO
• Angle gauge
Use goods on the market.
This tool is used to tightening the torque.
• Steering linkage alignment plate
P/N: YS-01515
90890-01515
Locks steering relay arm and pivot arm shaft in place while adjusting the
steering linkage for front-end alignment.
FOR ENGINE SERVICE
• Piston pin puller
P/N: YU-01304
90890-01304
This tool is used to remove the piston pin.
• Rotor holding puller
P/N: YU-33270-B
90890-01362
• Flywheel puller attachment
P/N: YM-33282
90890-04089
These tools are used to remove the magneto rotor.
1-4
GEN
SPECIAL TOOLS
• Cooling system tester
P/N: YU-24460-01
90890-01325
• Adapter
P/N: YU-33984
90890-01352
This tester and its adapter are used for checking the cooling system.
• Oil filter wrench
P/N: YM-01469
90890-01469
This tool is needed to loosen or tighten the oil filter cartridge.
INFO
• Vacuum gauge
P/N: YU-44456
90890-03094
This guide is used to synchronize the carburetors.
This tool is used for removing the primary sheave.
• Clutch spider separator
P/N: YS-28890-C
90890-01711
This tool is used when disassembling and assembling the primary sheave.
• Clutch separator adapter
P/N: YS-34480
90890-01740
This tool is used when disassembling and assembling the primary sheave.
• YXR clutch bushing jig kit
P/N: YS-39752
This tool is used for removal and installation of primary clutch weight and
roller bushings.
1-7
GEN
SPECIAL TOOLS
• Clutch bushing press
P/N: YS-42424
This tool is used for removing and installing the post bushings (primary
sheave cap bush, sliding sheave bush and torque cam bush).
• Track clip installer
P/N: YS-91045-C
90890-01721
This tool is used for installing the track clip.
FOR FUEL INJECTION SERVICE
• Mity vac
P/N: YS-42423
90890-06756
This tool is used to measure the vacuum pressure.
INFO
• Fuel pressure adapter
P/N: YM-03176
90890-03176
This tool is needed to measure fuel pressure.
• Pressure gauge
P/N: YU-03153
90890-03153
This tool is used to measure fuel pressure.
• Vacuum gauge
P/N: YU-08030
90890-03094
This guide is used to synchronize the throttle bodies.
FOR ELECTRICAL SERVICE
• Pocket tester
P/N: YU-03112-C
90890-03112
This instrument is necessary for checking the electrical components.
• Engine tachometer
P/N: YU-08036-C
90793-80009
This tool is used to check engine speed.
1-8
GEN
SPECIAL TOOLS
• Digital circuit tester
P/N: YU-A1927
90890-03174
This instrument is necessary for checking the electrical componenets.
INFO
1-9
INSP
ADJ
INTRODUCTION/PERIODIC MAINTENANCE CHART FOR
THE EMISSION CONTROL SYSTEM
PERIODIC INSPECTION AND ADJUSTMENT
INTRODUCTION
This chapter includes all information necessary to perform recommended inspections and adjustments. These
preventive maintenance procedures, if followed, will ensure more reliable machine operation and a longer service life. In addition, the need for costly overhaul work will be greatly reduced. This information applies to
machines already in service as well as new machines that are being prepared for sale. All service technicians
should be familiar with this entire chapter.
PERIODIC MAINTENANCE CHART FOR THE EMISSION CONTROL SYSTEM
ItemRemarks
Spark plugs
∗
Valve clearance
∗
Crankcase breather system
∗
Fuel filter
∗
Fuel line
∗
Idle speedCheck and adjust engine idle speed.
∗
Fuel injectionAdjust synchronization.
∗
Exhaust system
∗
It is recommended that these items be serviced by a Yamaha dealer.
Check condition.
Adjust gap and clean.
Replace if necessary.
Check clearance.
Adjust clearance when engine is cold.
Check breather hose for cracks or damage.
Replace if necessary.
Check condition.
Replace if necessary.
Check fuel hose for cracks or damage.
Replace if necessary.
Check for leakage.
Tighten or replace gasket if necessary.
Initial
Pre-opera-
tion check
(Daily)
Every 40,000 km (25,000 mi)
1 month or
800 km
(500 mi)
(40 hr)
Every
Seasonally
or 4,000 km
(2,500 mi)
(200 hr)
2
2-1
INSP
ADJ
GENERAL MAINTENANCE AND LUBRICATION CHART
GENERAL MAINTENANCE AND LUBRICATION CHART
ItemRemarks
Engine oil
∗
Engine oil filter cartridgeReplace.
FuelCheck fuel level.
Engine coolant
Throttle lever (handlebar
side)
Throttle override system
(T.O.R.S.)
Engine stop switch
Drive guard
V-belt
Drive track and idler wheels
Slide runners
Brake and parking brake
∗
Disc brake installation
Drive chain oil
Drive chain
Skis and ski runners
Steering system
Strap (PZ50M)
Lights
∗
Battery
∗
Primary and secondary
clutches
∗
Steering column bearingLubricate with specified grease.
∗
Ski and front suspensionLubricate with specified grease.
∗
It is recommended that these items be serviced by a Yamaha dealer.
Check oil level.
∗
Replace.
Check coolant level.
∗
Air bleed the cooling system if necessary.
Check operation.
∗
Repair if necessary.
Check operation.
∗
Repair if necessary.
Check operation.
∗
Repair if necessary.
Check for cracks, bends or damage.
∗
Replace if necessary.
Check for wear and damage.
Replace if necessary.
Check deflection, and for wear and damage.
∗
Adjust/replace if necessary.
Check for wear and damage.
∗
Replace if necessary.
Check operation and fluid leakage.
∗
Adjust free play and/or replace pads if necessary.
∗
Replace brake fluid.See NOTE on page 2-3.
Check for slight free play.
Lubricate shaft with specified grease as required.
Check oil level.
∗
Replace.
Check deflection.
∗
Adjust if necessary.
Check for wear and damage.
∗
Replace if necessary.
Check operation.
∗
Adjust toe-out if necessary.
Check for damage.
∗
Replace if necessary.
Check operation.
Replace bulbs if necessary.
Check condition.
Charge if necessary.
Check engagement and shift speed.
Adjust if necessary.
Inspect sheaves for wear/damage.
Inspect weights/rollers and bushings for wear-for primary.
Inspect ramp shoes/bushings for wear-for secondary.
Replace if necessary.
Lubricate with specified grease.
Initial
Pre-opera-
tion check
(Daily)
1 month or
800 km
(500 mi)
(40 hr)
Initial at 500 km (300 mi) and every 800 km
(500 mi) thereafter.
Whenever operating elevation is changed.
Every
Seasonally
or 4,000 km
(2,500 mi)
(200 hr)
Every
20,000 km
(12,000 mi)
Every
1,600 km
(1,000 mi)
2-2
INSP
ADJ
GENERAL MAINTENANCE AND LUBRICATION CHART
Every
Seasonally
or 4,000 km
(2,500 mi)
(200 hr)
ItemRemarks
∗
Suspension componentLubricate with specified grease.
∗
Parking brake cable end
and lever end/throttle cable
end
Shroud and covers
Fittings and fasteners
Tool kit and recommended
equipment
∗
It is recommended that these items be serviced by a Yamaha dealer.
NOTE:
@
Lubricate with specified grease.
Check cable damage.
Replace if necessary.
Make sure that the shroud and covers are securely fas-
tened.
Check tightness.
∗
Repair if necessary.
Check for proper placement.
Pre-opera-
tion check
(Daily)
Initial
1 month or
800 km
(500 mi)
(40 hr)
Brake system:
• After disassembling the master cylinder or caliper cylinder, always change the brake fluid. Regularly check
the brake fluid level and add fluid if necessary.
• Replace the oil seals of the master cylinder and caliper cylinder every two years.
• Replace the brake hose every four years, or if cracked or damaged.
2-3
INSP
ADJ
SPARK PLUGS/FUEL LINE INSPECTION
ENGINE
SPARK PLUGS
1. Remove:
• Fuel tank
Refer to “SEAT AND FUEL TANK” in CHAPTER 5. (PZ50/PZ50GT/PZ50FX/PZ50M)
Refer to “RIDER SEAT AND FUEL TANK” in
CHAPTER 5. (PZ50VT/PZ50MP)
2. Remove:
• Spark plug caps
• Spark plugs
3. Inspect:
• Electrodes 1
Damage/wear → Replace the spark plug.
• Insulator color 2
Abnormal color → Replace the spark plug
Normal color is medium-to-light tan.
4. Measure:
• Spark plug gap a
Out of specification → Regap.
Use a wire thickness gauge.
1
Spark plug gap:
0.6 ~ 0.7 mm (0.024 ~ 0.028 in)
If necessary, clean the spark plugs with a spark
plug cleaner.
Standard spark plug:
NGK R CR9EKB (NGK)
Before installing a spark plug, clean the gasket surface and spark plug surface.
5. Install:
• Spark plugs
Spark plug:
13 Nm (1.3 m · kg, 9.4 ft · lb)
T
.
R
.
NOTE:
Finger-tighten a the spark plug before torquing
it to specification.
b
FUEL LINE INSPECTION
1. Remove:
• Headlight assembly (PZ50/PZ50GT/PZ50FX/
PZ50M)
Refer to “COWLINGS” in CHAPTER 3.
2. Inspect:
• Fuel hose 1
• Fuel return hose
Cracks/damage → Replace.
2-4
INSP
ADJ
1
COOLING SYSTEM
COOLING SYSTEM
Coolant replacement
NOTE:
The coolant should be changed at least every season.
1. Place the machine on a level surface.
2. Remove:
• Right side panel
• Right side cover
Refer to “COWLINGS” in CHAPTER 3.
3. Remove:
• Coolant filler cap 1
WARNING
Do not remove the coolant filler cap 1 when the
engine is hot. Pressurized scalding hot fluid
and steam may be blown out, which could
cause serious injury. When the engine has
cooled, place a thick rag or a towel over the
coolant filler cap. Slowly turn the cap counterclockwise until it stop. This allows any residual
pressure to escape. When the hissing sound
has stopped, press down on the cap while turning it counterclockwise to remove it.
4. Place an open container under the radiator outlet hose 1.
5. Disconnect:
• Radiator outlet hose 1 1
6. Drain the coolant.
NOTE:
Lift up the tail of the machine to drain the coolant.
1
WARNING
Coolant is poisonous. It is harmful or fatal if
swallowed.
• If coolant is swallowed, induce vomiting
immediately and get immediate medical attention.
• If coolant splashes in your eyes, thoroughly
wash them with water and consult a doctor.
• If coolant splashes on your skin or clothes,
quickly wash it away with soap and water.
2-5
INSP
ADJ
COOLING SYSTEM
7. Connect:
• Radiator outlet hose 1
8. Fill:
• Cooling system
Recommended coolant:
High quality silicate-free ethylene
glycol antifreeze containing corrosion inhibitors
Coolant mixing ratio (coolant:water):
3:2 (60%:40%)
Total amount:
PZ50/PZ50GT/PZ50FX/PZ50M
3.6 L (3.17 Imp qt, 3.81 US qt)
PZ50VT/PZ50MP
3.7 L (3.26 Imp qt, 3.91 US qt)
CAUTION:
• Hard water or salt water is harmful to engine
parts. If soft water is not available, use boiled
or distilled water.
• Do not use water containing impurities or oil.
1
3
2
9. Bleed the air from the cooling system.
10. Inspect:
• Cooling system
Decrease of pressure (leaks) → Repair as
required.
Inspection steps:
• Attach the cooling system tester 1 and adapter
to the coolant filler 3.
2
Cooling system tester:
90890-01325, YU-24460-01
Adapter:
90890-01352, YU-33984
• Apply 100 kPa (1.0 kg/cm
• Measure the pressure with the gauge.
2-6
2
, 14 psi).
INSP
ADJ
COOLING SYSTEM/VALVE CLEARANCE ADJUSTMENT
1
Air bleeding steps:
• Remove the cap 1 on the radiator outlet pipe 1.
• While slowly adding coolant to the coolant filler,
drain the coolant until no more air bubbles
appear.
• Install the cap 1.
• Add coolant to the full level a.
• Install the coolant filler cap.
Apply and lock the parking brake. Start the
engine and run it at approximately 1,700 ~
3,500 r/min until the coolant circulates (approximately 3 ~ 5 minutes). The heat exchanger will
be warm to the touch.
WARNING
To avoid severe injury or death:
• Make sure the machine is securely supported
with a suitable stand.
• Do not exceed 3,500 r/min. Drive line damage
and excessive V-belt wear could occur, or the
machine could unexpectedly move forward if
the clutch engages.
• Operate the engine only in a well-ventilated
area.
2
b
• Remove the coolant filler cap and bleed the
cooling system again, as described above.
No air bubbles → OK.
• Pour coolant into the coolant reservoir 2 until
the coolant level reaches the “COLD LEVEL”
mark b.
VALVE CLEARANCE ADJUSTMENT
NOTE:
• Valve clearance adjustment should be made on a
cold engine, at room temperature.
• When the valve clearance is to be measured or
adjusted, the piston must be at the top dead center (TDC) on the compression stroke.
1. Drain:
• Engine oil
Refer to “ENGINE OIL REPLACEMENT”.
2. Remove:
• Fuel tank
Refer to “SEAT AND FUEL TANK” in CHAPTER 5. (PZ50/PZ50GT/PZ50FX/PZ50M)
Refer to “RIDER SEAT AND FUEL TANK” in
CHAPTER 5. (PZ50VT/PZ50MP)
• Oil tank
Refer to “A.C. MAGNETO ROTOR AND
STARTER CLUTCH” in CHAPTER 5.
2-7
INSP
ADJ
b
1
2
a
VALVE CLEARANCE ADJUSTMENT
3. Remove:
• Cylinder head cover
Refer to “CAMSHAFTS” in CHAPTER 5.
• Timing mark accessing screw 1
• Crankshaft end accessing screw 2
4. Measure:
• Valve clearance
Out of specification → Adjust.
Valve clearance (cold):
Intake valve:
0.11 ~ 0.20 mm
(0.0043 ~ 0.0079 in)
Exhaust valve:
0.21 ~ 0.25 mm
(0.0083 ~ 0.0098 in)
Checking steps:
• Turn the crankshaft counterclockwise.
• When piston #1 is at TDC on the compression
stroke, align the TDC mark a on the A.C. magneto rotor with the mark b on the A.C. magneto
cover.
1
NOTE:
TDC on the compression stroke can be found when
the camshaft lobes are turned away from each
other.
• Measure the valve clearance with a thickness
gauge 1.
NOTE:
• If the valve clearance is incorrect, record the
measured reading.
• Measure the valve clearance in the following
sequence.
Valve clearance measuring sequence
Cylinder #1 → #2
• Turn the crankshaft 180° counterclockwise and
check the valve clearance of piston #2.
Front
È
2-8
INSP
ADJ
VALVE CLEARANCE ADJUSTMENT
5. Remove:
• Intake camshaft
• Exhaust camshaft
NOTE:
• Refer to “CAMSHAFTS” in CHAPTER 5.
• When removing the timing chain and camshafts,
fasten a wire to the timing chain to retrieve it if it
falls into the crankcase.
6. Adjust:
• Valve clearance
Adjustment steps:
• Remove the valve lifter 1 and the valve pad
with a valve lapper 3.
NOTE:
• Cover the timing chain opening with a rag to prevent the valve pad from falling into the crankcase.
• Make a note of the position of each valve lifter
and valve pad 2 so that they can be installed in
the correct place.
2
1
• Select the proper valve pad from the following
table.
Valve pad thickness
range
1.20 ~
Nos.
120 ~ 240
2.40 mm
(0.047 ~
0.094 in)
Available valve pads
25 thicknesses in
0.05 mm (0.0020 in)
increments
NOTE:
• The thickness a of each valve pad is marked in
hundredths of millimeters on the side that
touches the valve lifter.
• Since valve pads of various sizes are originally
installed, the valve pad number must be rounded
in order to reach the closest equivalent to the
original.
• Round off the original valve pad number
according to the following table.
Last digitRounded value
0 or 20
55
810
2-9
INSP
ADJ
VALVE CLEARANCE ADJUSTMENT
EXAMPLE:
Original valve pad number = 148 (thickness =
1.48 mm (0.058 in))
Rounded value = 150
• Locate the rounded number of the original valve
pad and the measured valve clearance in the
valve pad selection table. The point where the
column and row intersect is the new valve pad
number.
NOTE:
The new valve pad number is only an approximation. The valve clearance must be measured again
and the above steps should be repeated if the measurement is still incorrect.