Troubleshooting - Honda 1998 VT750C Service Manual

CYLINDER HEAD/VALVES
TROUBLESHOOTING
• Engine top-end problems usually affect engine performance. These can be diagnosed by a compression test, or by
tracking noises to the top-end
• If performance is poor at low speeds, check for white smoke in the crankcase breather tube. If the tube is smoky, check
for a seized piston ring.
Compression too low, hard starting or poor performance
at low speed
Valves
-Incorrect valve adjustment
- Burned or bent valves
-Incorrect valve timing
- Broken valve spring
- Uneven valve seating
Cylinder head
- Leaking or damaged cylinder head gasket
- Warped or cracked cylinder head
Loose spark plug
Faulty cylinder, piston (Section 11)
Compression too high
• Excessive carbon build-up in cylinder head or on top of
piston
Excessive smoke
• Worn valve stem or valve guide
• Damaged stem seal
• Faulty cylinder, piston (Section 11)
Excessive noise
• Incorrect valve adjustment
• Sticking valve or broken valve spring
• Damaged or worn camshaft
• Loose or worn cam chain
• Worn or damaged cam chain tensioner
• Worn cam sprocket teeth
• Faulty cylinder, piston (Section 11)
Rough idle
• Low cylinder compression
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