Engine Oil Level Inspection - Yamaha YFM250XL(C) Service Manual

COMPRESSION PRESSURE MEASUREMENT/

ENGINE OIL LEVEL INSPECTION

If pressure falls below the minimum level:
1) Squirt a few drops of oil into the affected
cylinder.
2) Measure the compression again.
Compression pressure
(with oil introduced into cylinder)
Reading
Higher than with-
out oil
Same as without
oil
Above maximum
level
Remove the compression gauge.
**********************************
4.Install:
Spark plug
Spark plug:
17.5 Nm (1.75 m • kg, 12.5 ft • lb)
Refer to "SPARK PLUG INSPECTION" sec-
tion.
ENGINE OIL LEVEL INSPECTION
CAUTION:
Do not add any chemical additives.
Engine oil also lubricates the clutch and
additives could cause clutch slippage.
Do not allow foreign material to enter the
crankcase.
1.Place the machine on a level place.
2.Inspect:
Engine oil level
Oil level low → Add sufficient oil
**********************************
Inspection steps:
Warm up the engine for several minutes,
and stop it, then wait at least several min-
utes for the oil to drain back into the
crankcase.
3 - 19
INSP
ADJ
Diagnosis
Worn or damaged cyl-
inder or rings
Defective ring(s),
valves, cylinder head
gasket.
Inspect cylinder head,
valve surface, or pis-
ton crown for carbon
deposit.
3