QUANCHAI N485D, Maintenance Manual

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ANHUI QUANCHAI ENGINE CO., LTD
bottom dead center 50±3°
Switched-off exhaust valve after top
dead center 14±3°
10
Fuel injector
seat
There is no air leakage on the contact
surface between the fuel injector and the
cylinder cover. The fuel injector seat leaks air,
affecting combustion. Please
replace the fuel injector seat.
11 Cylinder head
The torque of the cylinder head bolt is
145-155 N.m.
The loose cylinder head bolts
affect compression combustion
working. Please check the cylinder
head bolts and re-tighten them to
the specified torque range.
12 Piston ring
The piston ring wears down within a
reasonable range and there is no carbon
deposit on it.
The piston ring is filled with
carbon deposit, jammed or worn.
All these cases affect power.
Replace the piston ring.
13
Cylinder head
gasket
The cylinder head gasket has a
compaction thickness of 1.2
±0.08 mm

(with tightening torque of 150 N•m).
The air leakage of the cylinder
head gasket affect compression
combustion working. Please
replace the cylinder head gasket.