Yamaha FZS1000N, Service Manual

Page: 81 / 394

3-18
MEASURING THE COMPRESSION PRESSURE
CHK
ADJ
WARNING
NOTE:
13 Nm (1.3 m kg, 9.4 ft lb)
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.
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/cm2, 206 psi)
Minimum:
1,260 kPa (12.6 kg/cm
2
, 179 psi)
Maximum:
1,620 kPa (16.2 kg/cm
2
, 230 psi)
a. Turn the main switch to “ON”.
b. With the throttle wide open, crank the engine
until the reading on the compression gauge
stabilizes.
To prevent sparking, ground all spark plug
leads before cranking the engine.
The difference in compression pressure be-
tween cylinders should not exceed 100 kPa (1
kg / cm
2
,14.2 psi).
7. Install:
spark plug
8. Connect:
spark plug cap