KAYO MOTOR TD125, Service Manual

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6
Clearance between valve
rod and valve guide
Intake valve 0.013~0.04 0.07
Exhaust valve 0.025~0.052 0.08
7 Width of valve sealing tape 1.5 /
8 Flatness of cylinder head 0.04 0.05
Width of cylinder head valve seat face 0.8 /
Fault symptom and cause analysis
No. Fault symptom Cause analysis Remarks
1 Low pressure in the cylinder
Valve clearance is too small
The valve seat is not tight
The valve timing is wrong
The valve spring is broken
Leakage of spark plug and cylinder head
mounting parts
The cylinder head gasket combination is not
tight
Crack or sand hole in cylinder head
Piston ring clearance is too large or broken
The piston has cracks or excessive wear
The inner diameter of the cylinder block is too
large or sand holes
2 Black smoke in the exhaust
Valve guide worn
Leakage or damage to oil cap
Piston ring clearance is too large
Leakage of cylinder head gasket assembly
3 Excessive and abnormal noise
Valve clearance is too large
The valve is stuck or the valve spring is broken
Excessive wear of rocker arm
Incorrect valve timing
Camshaft wore
Removal of left cover of cylinder head
Small inspect hole
Left cover of cylinder Big inspect hole
1.Remove the cylinder head left cover bolt,
2.Remove engine cylinder head left cover and left cover
gasket,
3.Remove the cover of small and big inspect hole.