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CHECKING THE END COMPRESSION PRESSURE
- With the engine cold, remove the spark plug cap
- Remove the spark plug.
- Fit a compression testing pressure gauge in the spark plug seat with a spark plug fitting and tighten it.
- Run the engine using the starter motor and with the carburettor fully open, until the reading on the pressure gauge
is stable.
- If the pressure is normal, remove the device and reassemble the dismantled parts.
- If the pressure readings are below those indicated, check the rpm used for the test, if it is low, check the starter
system. If the number of rpm is perfect or slightly above, make sure the correct seal has been chosen for the cyl-
inder base and check the seals of the thermal part ( elastic bands- valves etc...)
IF YOU HAVE A HARD TIME INSERTING THE PRESSURE GAUGE FITTING, DISCONNECT THE ENGINE-
SWING ARM CONNECTION PIN AND PULL BACK THE ENGINE AS REQUIRED TO INSERT THE FITTING.
Technical specifications
Spark plug fitting
10 mm
Rpm
~ 800 rpm (starting speed).
Compression end pressure
14 ÷ 15 BAR