Cylinder Compression Test; Cylinder Head Cover Removal - Honda CRF110F Service Manual

CYLINDER HEADNALVES
CYLINDER COMPRESSION TEST
Warm up the engine 10 normal operating temperature.
Slop the engine and disconnect the spark plug cap.
Remove the spark plug (page 3-8).
Install the compression gauge {1] in the spark plug hole.
Tum the Ignition switch ON and engine stop switch to
"0'.
Shift the transmission into neutral.
Open the throttle all the way and crank the engine with
the electric starter until the gauge reading stops rising.
STANDARD :
1,412 kPa (14.4 kgflcm
2
,
205 psi) at 400 rpm
1 11
If compression is high, it indicates that carbon deposits ' - - - - - - - - - - - - - -- -- - - - - '
have accumulated on the combustion chamber and/or
the piston head .
If compression is low, pour 3 - 5 cm
3
(0.1 - 0.2 oz) of
engine oil into the cylinder through the spark plug hole
and recheck the compression.
If the compression increases from the previous value ,
check the cylinder, piston and piston rings for the
following:
- leaking cylinder head gasket
- Worn piston ring
- Worn
cylinder and piston
If the compression Is the same as the previous value ,
check the valves for leakage,
CYLINDER HEAD COVER
REMOVAL
8-6
Remove the special bolts [1), mounting rubbers
[21
and
cylinder head cover [3},
Remove the rubber seal [1] and dowel pin [2] from the
cylinder head cover [3).
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