Honda 954 Service Manual page 252

CYLINDER HEADNALVES
CYLINDER COMPRESSION TEST
Warm up the engine to normal operating tempera-
ture.
Stop the engine and remove all the direct ignition
Open and support the front end of the fuel tank (page
Disconnect the fuel pumpireserve sensor 3P (Black)
connector.
Install a compression gauge into the spark plug hole.
TOOL:
Compression gauge attachment
Open the throttle all the w a y and crank the engine
with the starter motor until the gauge reading stops
rising.
The maximum reading is usually reached within 4
To avoiddischarg-
ing the battery, do
not operate the
Compression pressure:
1,196 kPa (12.2 kgf/crn2, 174 psi) at 350 rpm
7
seconds
Low compression can be caused by:
- Blown cylinder head gasket
- Improper valve adjustment
-
Valve leakage
-
Worn piston ring or cylinder
High compression can be caused by:
-
Carbon deposits in combustion chamber or on pis-
ton head
07RMJ-MY50100
(Equivalent cornrner-
-
7
3P (BLACK) CONNECTOR
COMPRESSION GAUGE