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Snowmobile Yamaha Phazer PZ50W, PZ50GTW, PZ50FXW, PZ50MW, PZ50VTW, PZ50MPW. Manual - part 7

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THROTTLE CABLE FREE PLAY ADJUSTMENT/

THROTTLE OVERRIDE SYSTEM (T.O.R.S.) CHECK

• Tighten the locknut.

NOTE:

If the specified throttle cable free play cannot be
obtained on the throttle body side of the cable, use
the adjusting nut on the handlebar side. (PZ50/
PZ50GT/PZ50FX/PZ50M)

Handlebar side adjustment steps:
(PZ50/PZ50GT/PZ50FX/PZ50M)

• Loosen the locknut 1.
• Turn the adjusting nut 2 in or out until the spec-

ified free play is obtained.

NOTE:

After adjusting the free play, turn the handlebar to
right and left, and make sure that the engine idling
does not run faster.

THROTTLE OVERRIDE SYSTEM (T.O.R.S.)
CHECK

WARNING

When checking T.O.R.S.:
• Be sure the parking brake is applied.
• Be sure the throttle lever moves smoothly.
• Do not run the engine up to the clutch

engagement speed. Otherwise, the machine
could start moving forward unexpectedly,
which could cause an accident.

1. Start the engine.
2. Hold the pivot point of the throttle lever away

from the throttle switch by putting your thumb
(above) and forefinger (below) between the
throttle lever pivot 1 and stop switch housing
2.
While holding as described above, press the
throttle lever 3 gradually.
The T.O.R.S. will operate and the engine
should run between 2,800 and 3,000 r/min.

Turning in

→ Free play is increased.

Turning out

→ Free play is decreased.

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THROTTLE OVERRIDE SYSTEM (T.O.R.S.) CHECK/

COMPRESSION PRESSURE MEASUREMENT

WARNING

If the engine does not run between 2,800 and
3,000 r/min, stop the engine by turning the main
switch to the “OFF” position and check the
electrical system.

COMPRESSION PRESSURE
MEASUREMENT

NOTE:

Insufficient compression pressure will result in a
loss of performance.

1. Measure:

• Valve clearance

Out of specification

→ Adjust.

Refer to “VALVE CLEARANCE ADJUST-
MENT”.

2. Start the engine, warm it up for several minutes,

and then turn it off.

3. Remove:

• Fuel tank

Refer to “SEAT AND FUEL TANK” in CHAP-
TER 5. (PZ50/PZ50GT/PZ50FX/PZ50M)
Refer to “RIDER SEAT AND FUEL TANK” in
CHAPTER 5. (PZ50VT/PZ50MP)

4. Remove:

• Spark plug

CAUTION:

Before removing the spark plugs, use com-
pressed air to blow away any dirt accumulated
in the spark plug wells to prevent it from falling
into the cylinders.

5. Install:

• Compression gauge 1

Compression gauge:

90890-03081, YU-33223

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COMPRESSION PRESSURE MEASUREMENT

6. Measure:

• Compression pressure

Above the maximum pressure

→ Inspect the

cylinder head, valve surfaces, and piston
crown for carbon deposits.
Below the minimum pressure

→ Squirt a few

drops of oil into the affected cylinder and
measure again.
Refer to the following table.

Measurement steps:

• Turn the main switch to “START”.
• With the throttle wide open, crank the engine

until the reading on the compression gauge sta-
bilizes.

WARNING

To prevent sparking, ground all ignition coil
leads before cranking the engine.

NOTE:

The difference in compression pressure between
cylinders should not exceed 100 kPa (1 kg/cm

14.2 psi).

7. Install:

• Spark plug

Compression pressure

(with oil applied into cylinder)

Reading

Diagnosis

Higher than
without oil

Piston ring(-s) wear or
damage

→ Repair.

Same as
without oil

Piston, valves, cylinder
head gasket or piston
possibly defective

→

Repair.
Compression pressure (at
sea level)

Compression pressure (at sea level):

Standard:

1,450 kPa (14.5 kg/cm

, 206 psi)

at 400 r/min

Minimum:

1,260 kPa (12.6 kg/cm

, 179 psi)

at 400 r/min

Maximum:

1,620 kPa (16.2 kg/cm

, 230 psi)

at 400 r/min

Spark plug:

13 Nm (1.3 m · kg, 9.4 ft · lb)

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ENGINE OIL LEVEL INSPECTION

1. Inspect:

• Engine oil level

CAUTION:

Do not run the engine with too much or not
enough oil in the oil tank. Oil could flow into the
air filter and the engine could be damaged.

Inspection steps:

• Place the snowmobile on a level surface and

apply the parking brake.

• Start the engine, warm it up for 10 ~ 15 minutes,

and then turn off.

• Remove the right side cover.

Refer to “COWLINGS” in CHAPTER 3.

• Disconnect the oil level switch coupler 1.

CAUTION:

Disconnect the oil level switch coupler before
removing the oil level gauge. Otherwise the
lead can twist and become severed.

• Remove the oil level gauge/dipstick 2, wipe it

clean, insert it back into the filler hole (without
screwing it in), and then remove it again to
check the oil level.

• The engine oil level should be between the

maximum level mark “H”

a and minimum level

mark “L”

Below the minimum level mark

→ Add the rec-

ommended engine oil to the proper level.

CAUTION:

When adding the engine oil, be careful not to fill
above the maximum level mark and minimum
level mark on the oil level gauge.

CAUTION:

Do not allow foreign materials to enter the
crankcase.

NOTE:

Before checking the engine oil level, wait a few
minutes until the oil has settled.

Recommended oil:

Refer to the chart for the engine oil
grade which is best suited for cer-
tain atmospheric temperatures.

API standard:

API SE, SF, SG or higher
SAE 0W-30

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