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35
Fuel supply pump does not apply
fuel or applies fuel irregularly
Check for leakage of the delivery valve and
inspect whether injector is worn-out, plunger is
seized, and if plunger spring and delivery valve
spring is broken. Remove them in time.
Insufficient compression
pressure due to piston ring or
Cylinder much worn-out;
Check and replace the piston ring or Cylinder
Blow-by valve
Check the valve clearance and seal of valve.
Grind or readjust the valve if necessary.
Incorrect
fuel
injection
advance angle
Check and adjust it
Incorrect valve timing
For the overhauled engine, pay attention to the
timing marks alignment on timing gears.
Insufficient power output
Possible causes
Remedies
Oil advance angle changes
Check and adjust according to regulation
Faulty injector
Check the working pressure or atomization
of the injector, replace the needle valve precision
pair if necessary.
Incorrect intake and exhaust valve
clearance or bad seal of valve
Check and adjust the valve clearance according
to prescription; check the seal of the valve, grind
it if necessary