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16
0.65 mm
(0.026 in.)
COOLING
SYSTEM
Level 2.
Tools required:
25-50 mm (1-2 in.) cleaning brush, 4 mm Hex
Wrench, pointed wood stick.
Parts Required: None, if you are careful.
IMPORTANT
To maintain proper engine operating temperatures, cooling air must
pass freely through the cylinder fin area. This flow of air carries
combustion heat away from the engine.
Overheating and engine seizure can occur when:
• Air intakes are blocked, preventing cooling air from reaching the
cylinder.
• Dust and grass build up on the outside of the cylinder. This build up
insulates the engine and prevents the heat from leaving.
Removal of cooling passage blockages or cleaning of cooling fins is
considered “Normal Maintenance”. Any failure attributed to lack of
maintenance is not warranted.
Cleaning Grill
1.
Brush accumulated debris from crankcase intake grill above the
fuel tank.
SPARK
PLUG
Level 2.
Tools required:
T-Wrench, Feeler gauge
Parts Required:
Spark plug NGK BPM-8Y
IMPORTANT
Use only NGK BPM-8Y spark plug otherwise severe engine
damage may occur.
1.
Remove spark plug and check for fouling, worn and rounded
center electrode.
2.
Clean the plug or replace with a new one. DO NOT sand blast to
clean. Remaining sand will damage engine.
3.
Adjust spark plug gap by bending outer electrode.
4.
Tighten spark plug to 150-170 kg/cm (130-150 in. lb.).
Summary of Contents for PB-251
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