Zenoah G300PUM Owner's Manual page 19

13. Trouble Shooting
2) LACK OF POWER OR UNSTABLE RUNNING
Description
Overheating
Others
Cause
1. Air penetration from fuel pipe joints, etc
2. Air penetration from intake tube joint or
carburetor joint
3. Water in fuel
4. Piston start to seizure
5. Muffler choked with carbon
1. Fuel too lean
2. Clogging of cylinder fin with dust
3. Poor fuel quality
4. Carbon deposited in the combustion chamber
5. Spark plug electrode red hot
1. Dirty air cleaner
2. Over loading
Countermeasure
Secure connection
Change gasket or tightening screws
Change with good fuel
Replace piston(and cylinder)
Cleaning
Adjust carburetor
Cleaning
Exchange with proper fuel
Cleaning
Thoroughly clean, adjust spark gap
[ 0.6~0.7(0.023~0.028in) ]
Wash with mixed gasoline
Reduce load
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