(3) Valve free movement noise is caused by dropped valve keeper or broken valve head. It shall be replaced;
(4) Noise between the intake & exhaust valve and valve bushing is caused by stagnation valve and bushing
that can not be closed, repair the bushing or replace it;
(5) Valve and valve seat can not be tightly closed and noise is generated, leading to abnormal engine operation.
Valve shall be grinded to fit, otherwise it shall be replaced.
3. Gear noise is mainly caused by excessive wear of the gear which results in excessive clearance,
generating the noise during the operation. The counter gear shall be replaced.
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