Linhai ATV 500-D T3 EFI, Service Manual

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CHAPTER 3 ENGINE
LH500ATV-D T3 EFI SERVICE MANUA 19.0
CHAPTER 3 ENGINE PAGE. 3- 65
Automatic Decompression
Move the automatic decompression weight with
hand and check if it is operating smoothly. If it is
not working smoothly, replace with a new
camshaft/automatic decompression assembly.
Cam Wear
Worn cams can often cause mistimed valve
operation resulting in reduced power output. The limit of
cam wear is specified for both IN and EX cams in terms
of cam height “a”. Measure with a micrometer the cam
height.
Cam height out of range:
→
Replace
Cam height service limit:
IN: 33.130mm
EX: 33.200mm
Tool : micrometer (25-50mm)
Camshaft Journal Wear
Check whether each journal is worn to the limit by
measuring camshaft journal oil clearance with the
camshaft installed.
Camshaft journal oil clearance
Service limit: 0.15mm
Check according to the following steps:
Clean off materials from cylinder head and cover;
Install camshaft with plastic gauge;
Install cylinder head cover and tighten bolts evenly
and diagonally to the specified torque:
Tightening torque: 10 N·m
Remove cylinder head cover, read the width of the
compressed plastic gauge with envelop scale. The
reading should be taken from the widest part.
Tool: Plastid Gauge
Note: Do not turn the camshaft with plastic gauge in
place.
If the camshaft journal oil clearance exceeds the limit,
measure the outer diameter of camshaft;
Replace either cylinder head set or the camshaft if the
clearance is not correct.