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Overheat engine
Check the level of cooling water, add enough
water if necessary; check for the leakage of the
water pump or the looseness of the belt,
remove or require it if necessary; check for
thickness of scale in water passage, remove it if
necessary.
Air cleaner choking
Replace the filter element.
Fuel supply pipe clogged
Check and clean it.
Faulty injection pump
Check for leakage of the delivery valve and
inspect whether plunger is worn-out, and if the
plunger spring and delivery valve spring is
broken, replace the damaged parts, cylinder
gasket and readjust oil pump if necessary.
Cylinder
gasket
damage
or
leakage
Replace it.
Too high exhaust back pressure
Clear the exhaust passage and muffler
Excessive blow-by
Check the piston, piston ring and cylinder sleeve.
If they are much worn out or ring elasticity is
insufficient, replace them.
Intake
pipe
leakage
(Turbocharger)
Check the oil pipe and remove leakage.
Turbocharger is out of order
Determine the location of the troubles and
remove it.