Inspection Of Compression Pressure - TOHATSU TLDI MD 115A SERIES Service Manual

3) Inspection of Compression Pressure

1. Start and idle engine for 5 minutes to warm up, and then stop.
2. Shift gear into neutral (N).
3. Remove lock plate (of stop switch lanyard) from stop switch.
To prevent accidental start of the engine, remove
lock plate (of stop switch lanyard) from stop switch
before measuring compression pressure.
4. Remove all plug caps and then all spark plugs.
Clean areas around spark plugs on the
cylinder before removing spark plugs to
prevent dirt from entering cylinder.
5. Install compression gauge to plug hole.
Compression Gauge:
P/N. 3AC-99030-0
6. Set free throttle lever to full open position, crank engine
until compression gauge indication stabilizes, and then
measure compression pressure.
Compression Pressure (Reference):
0.9 MPa (128 psi) [9.0 kgf/cm
Compression pressure is affected much by
cranking speed, and normally changes in the
range from 10% to 20%. Charge the battery.
7. If compression pressure is below specified value or varies
much among cylinders, put small amount of engine oil into
cylinders, and perform the test again.
· If compression pressure increases after the above
measure, check pistons and piston rings for wear.
Replace if necessary.
· Check cylinder head gasket if the compression pressure
does not rise. Adjust or replace if necessary.
If any of the following results is obtained by the measurement, it
is necessary to repair or replace relevant part(s).
· The measurement is lower than specified value,
· Different between compression pressure of the cylinders exceeds;
0.105 MPa (15 psi) [1.05 kgf/cm
· The measurement is abnormally higher than specified value.
TLDI 115A 2007
CAUTION
CAUTION
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