Honda GL1800 Service Manual page 752

TROUBLESHOOTING
8. Cylinder Compression Inspection
Test the cylinder compression.
Is the compression as specified?
NO
YES
9. Programmed Fuel Injection System Inspection
Check the fuel injection system.
Is the fuel injection system normal?
NO
YES
10. Lubrication Inspection
Remove cylinder head cover and inspect lubrication.
Is the valve train lubricated properly?
NO
YES
11. Overheating Inspection
Check for engine overheating.
Is the engine overheating?
YES
NO
12. Engine Knocking Inspection
Accelerate or run at high speed.
Is the engine knocking?
YES
NO
25-4
– • Valve clearance too small
• Worn cylinder and piston rings
• Damaged cylinder head gasket
• Improper valve timing
– GO TO STEP 9.
– Faulty fuel injection system (section 5)
– GO TO STEP 10.
– Clogged oil passage
– GO TO STEP 11.
– • Coolant level too low
• Fan motor not working (Faulty fan motor or ECM)
• Thermostat stuck closed
• Excessive carbon build-up in combustion chamber
• Use of poor quality fuel
• Clutch slipping
• Wrong type of fuel
– GO TO STEP 12.
– • Worn piston and cylinder
• Wrong type of fuel
• Excessive carbon build-up in combustion chamber
• Ignition timing too advanced (Faulty ECM)
– Engine does not knock