Yamaha F30B 2018, Service Manual

Page: 156 / 348

7-1
Power unit (check and adjustment)
Power unit (check and adjust-
ment)
Checking the compression pressure
1. Check:
• Compression pressure
Below specification

Check the engine
internal parts.
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a. Start the engine, warm it up for 5 minutes,
and then stop it.
b. Remove the clip from the engine shut-off
switch.
c. Disconnect the fuel injector couplers and
spark plug caps.
d. Remove all of the spark plugs.
e. Install the special service tools into the
spark plug hole.
Before removing the spark plugs, remove
any dirt or dust in the spark plug wells that
could fall into the cylinders.
f. Fully open the throttle.
g. Crank the engine until the reading on the
compression gauge stabilizes, and then
measure the compression pressure.
h. Remove the special service tools.
i. Install all of the spark plugs, and then tight-
en the spark plugs to the specified torque.
j. Connect the spark plug caps and fuel in-
jector couplers.
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Checking the oil pressure
1. Check:
• Oil pressure
Below specification

Check the engine
internal parts.
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a. Disconnect the oil pressure switch lead
from the oil pressure switch end.
b. Remove the oil pressure switch, and then
install an oil pressure gauge “1” to the oil
pressure switch installation hole.
c. Start the engine and warm it up until the
engine idle speed stabilizes at the speci-
fied engine idle speed range.
Compression pressure
Minimum (reference data)
840.0 kPa (8.40 kgf/cm², 121.8
psi)
Compression gauge “1”
90890-03160
Combination compression gauge
and cylinder leakdown test kit “1”
YB-45544-A
1
Spark plug
18 N·m (1.8 kgf·m, 13 lb·ft)
Engine oil pressure at idle speed
(reference data)
230.0 kPa (2.30 kgf/cm², 33.4
psi)
/ SL 10W-30 engine oil
Engine oil pressure at 3000 r/min
(reference data)
480.0 kPa (4.80 kgf/cm², 69.6
psi)
/ SL 10W-30 engine oil
Idle speed (in neutral)
750–850 r/min
T
R
.
.