KAYO MOTOR TD125, Service Manual

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ring0.1
~0.250
.43
4
50.4 Outside diameter of piston pin φ12.994~φ13 φ12.985
6
Inner diameter of tip of connecting
rod
φ13.016~φ13.027 Φ13.035
7
Clearance between connecting rod tip
and piston pin
0.016~0.033 0.05
Fault symptom and cause analysis
No Fault symptom cause analysis Remark
1
Low pressure in
cylinder
Abnormal wear of cylinder block or piston ring
2
Black smoke in the
exhaust
Abnormal wear of cylinder block, piston or piston
ring
The piston ring is not installed correctly
Scratches on the piston or cylinder wall
3 Engine overheat Excessive carbon accumulation in piston
4
Knock or abnormal
noise
The piston or cylinder is worn
Excessive carbon accumulation in piston
Removal of cylinder block
The removal steps of the cylinder are as follows:
1. Remove cylinder head;
2. Remove the fastening chain guide roller pin and
aluminum pad φ 8;
3. Remove the M6x23 cross groove connecting bolts
connecting the cylinder body and the crankshaft box;
4. Remove the cylinder body, cylinder body gasket and
O-ring.
Note:
1. If the cylinder body gasket is damaged, the remaining
gasket on the cylinder surface and the crankcase
cylinder surface should be scraped clean with a scraper.
Then replace with a new gasket. To prevent engine
leakage after reassembly.
2. The gasket is easy to disassemble if it is immersed in
gasoline. Avoid damage to cylinder contact surfaces
when doing this.
3. The removed parts should be properly placed to avoid
damage and loss.
Inspection of cylinder block