Service manual

03-24
✰ Hold the throttle open fully and kick
several times (5 to 6 times).
✰ Note down the reading and repeat
the above process 3 times. Take to
average mean reading in 100 ± 10
PSI which is the correct
compression pressure. Specified
engine compression pressure.
STEP-B
✰ In case compression pressure is less
than 80 PSI, then refit spark plug &
start again to warmup the engine.
✰ Switch “OFF” Ignition and engine
stop switch condition.
a) Remove spark plug & put few drops
of engine oil into the combustion
chamber.
b) Connect compression gauge &
repeat the procedure as explained in
the step-A.
✰ If compression pressure does not
increase, then check for
- blown out cylinder head gasket
- improper torque of Rocker
bearing
bolts or cylinder head nuts.
- valve seat - damage / leakage
- valvestem bend
- cylinder head warpage
- improper valve timing
✰ If compression pressure reading
increases, then check for
- Improper alignment of piston ring
(end gap position)
- piston ring jamed in groove.
- scoring / seizure of cylinder
barrel / piston
- worn out piston/rings
- worn out cylinder barrel
NOTE :
In case compression pressure is more
than 110 PSI then engine requires
Decarbonisation of cylinder head /
piston (combustion chamber).
DECARBONISING
(EVERY 30,000 KMS)
CYLINDER HEAD
✰ Remove carbon from the valves, ports
and combustion chamber by
scrapping. Take care not to cause
any damage to the valve faces or
valve seat inserts. Scrape gently to
avoid scoring the cylinder head.
Periodical Maintenance