Yamaha 2006 YZFR6V, Service Manual

Page: 105 / 444

ENGINE
3-10
6. Measure:
• Compression pressure
Out of specification
→
Refer to steps (c) and
(d).
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a. Set the main switch to “ON”.
b. With the throttle wide open, crank the engine
until the reading on the compression gauge
stabilizes.
WARNING
EWA12940
To prevent sparking, ground all spark plug
leads before cranking the engine.
NOTE:
The difference in compression pressure be-
tween cylinders should not exceed 100 kPa (1
kg/cm², 14 psi).
c. If the compression pressure is above the
maximum specification, check the cylinder
head, valve surfaces and piston crown for
carbon deposits.
Carbon deposits
→
Eliminate.
d. If the compression pressure is below the min-
imum specification, pour a teaspoonful of en-
gine oil into the spark plug bore and measure
again.
Refer to the following table.
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7. Install:
• Spark plugs
• Ignition coils
8. Install:
• Radiator
Refer to “RADIATOR” on page 6-1.
• Bottom cowlings
• Side cowlings
Refer to “GENERAL CHASSIS” on page 4-1.
EAS20730
CHECKING THE ENGINE OIL LEVEL
1. Stand the vehicle on a level surface.
NOTE:
• Place the vehicle on a suitable stand.
• Make sure the vehicle is upright.
2. Start the engine, warm it up for several min-
utes, and then turn it off.
3. Remove:
• Dipstick “1”
4. Check:
• Engine oil level
The engine oil level should be between the
minimum level mark “a” and maximum level
mark “b”.
Below the minimum level mark
→
Add the
recommended engine oil to the proper level.
NOTE:
• Before checking the engine oil level, wait a few
minutes until the oil has settled.
• Do not screw the dipstick in when inspecting
the oil level.
Compression gauge
90890-03081
Engine compression tester
YU-33223
Extension
90890-04136
Standard compression pressure
(at sea level)
1550 kPa/400 r/min (220.5
psi/400 r/min) (15.5 kgf/cm²/400
r/min)
Minimum–maximum
1300–1600 kPa (184.9–227.6 psi)
(13.0–16.0 kgf/cm²)
1
2
Compression pressure (with oil applied into
the cylinder)
Reading Diagnosis
Higher than without
oil Piston ring(s) wear or
damage
→
Repair.
Same as without oil
Pistons, valves, cylin-
der head gasket or
piston ring(s) possi-
bly defective
→
Re-
pair.
T
R
.
.
Spark plug
13 Nm (1.3 m·kg, 9.4 ft·lb)