Linhai ATV 260 Service Manual page 113

CHAPTER 3B ENGINE 50cc/80cc
Valve bar outer diameter
Valve guide pipe
diameter
Gap between valve bar and
guide pipe
Valve spring
Torque Value
Camshaft bolt
Valve gap adjusting screw cap
Tools:
General tools
Valve spring compressor
Valve seat reamer
Valve seat reamer
Valve seat reamer
Valve seat reamer
Reamer damping fixture
Special tools
Valve spring compressor accessories
Valve gap regulatory spanner
Valve guide screwdriver
Valve guide reamer
Trouble diagnosis
●Confirm poor operation of cylinder head by
measuring pressure or by noise produced by
engine upper end.
Slow speed hitch
●too low compression pressure
●bad valve gap
●burning or curving of valve
●bad valve timing
●broken valve spring
●bad valve seat
●leakage of cylinder head gasket
●cylinder head surface warping or cracking
●bad spark plug
Too high compressed pressure
●too much carbon build-up in combustion
chamber
IN
EX
inner IN
EX
IN
EX
Inner spring
Outer spring
20N.m 15 ft .lbs
8N. m 6 ft .lbs
24.5mm
25mm
22mm
26mm
5mm
4.975-4.990
4.955-4.970
5.0-5.012
5.0-5.012
0.010-0.037
0.030-0.057
30.5
33.5
lubricate threads with oil
45° IN/EX
Plane reamer 30° IN
Plane reamer 32° EX
Plane reamer 60° IN/ EX
White smoke from exhaust pipe
●wearing of valve guide
●broken oil seal
Abnormal noise
●bad valve gap
●broken or burning of valve or valve spring
●wearing and breaking of camshaft
●wearing of inner chain adjusting plate
●wearing of camshaft and valve rocker arm
CHAPTER 3B ENGINE
ATV SERVICE MANUAL07.0
4.9
4.9
5.3
5.3
0.08
0.10
26.1
30.5
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