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Trouble shooting
Low or unstable compression Overheated
1 Abrasion on cylinder or piston ring 1. Carbon buildup in combustion chamber
or on piston
Smoky Abnormal knock
1.Abrasion on cylinder, piston or its rings 1. Knocking or abnormal sound
2.Incorrect installation of piston rings 2. Abrasion on cylinder or piston
3.Scratch on cylinder inner wall or piston 3.Carbon buildup on piston
Disassembly of cylinder body
Remove cylinder head
（
Refer to section 6th
）
Remove gasket and positioning pin
Remove cylinder body
Caution; No timing chain drop into crankcase
is allowed.
Clean up remains on cylinder surface by scraper.
Caution: Immerse into gasoline may lead to
easy work, while avoiding damage on contact
surface of cylinder.
Check cylinder
Check abrasion and damage on cylinder
Measure inner diameter in three positions, which are
A, B, and C points at top, middle and bottom of stroke
of piston respectively, whose two directions are
vertical to each other.
A=10 B=60 C=100
Standard data for cylinder bore is
：
78.00
～
78.01
Limita datum for maintenance is
：
78.1