Honda Magna VF750C, Service Manual

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Service Information
Troubleshooting
Camshaft Removal
Service Information
8-1
8-1
8-2
8.
Cylinder Head/Valves
Cylinder Head Removal/Installation
8-4
Cylinder Head Disassembly
I
Assembly
8-6
Camshaft Installation
8-8
•
Front and rea r cylinder head service ca n be done with the engine i n the fra me.
•
Camshaft lubricati ng oil is fed through oil passages i n the cylinder head. Clean the oil passages before assem bling
the cyli nder head. Fill the cylinder head oil pockets with the clean engine oil of the proper type and viscosity.
•
Clean a l l d i sassem bled pa rts with clean solvent and d ry them by blowi ng them off with com p ressed a i r before
inspection.
•
When disassem bli ng, mark and store the disassem bled parts to ensu re that they a re rei nsta l led i n thei r proper loca­
tions.
•
The cyli nder n u m beri ng is g iven below:
Troubleshooting
( 1 ) FRONT
..
•
Engine top-end problems usual ly affect engine performance. These ca n be diagnosed by a compression or leak down
test, or by tracing noises to the top-end with a sounding rod or stethoscope.
•
If performance is poor at low speeds, check for white smoke i n the crankcase breather tube. If there is smoke i n the
tube, check for a seized piston ring.
Compression Too Low, Hard Starting Or Poor
Performance At Low Speed
•
Va lves
- I ncorrect va lve adjustment
- Bu rned or bent va lves
- I ncorrect va lve timing
- Broken va lve spri ng
- Uneven va lve seati ng
•
Cyli n der head
- Leaking or damaged head gasket
- Wa rped or cracked cyli nder head
•
Cylinder/piston
- Worn, stuck or broken piston ring
- Worn or damage cyli nder and piston
Compression Too High, Overheating Or Knocking
•
Excessive carbon bui ld-up i n cylinder head or on top
of piston
Excessive Smoke
•
Cylinder head
- Worn va lve stem or valve guide
- Da maged stem seal
•
Cylinder, piston
- Worn cylinder, piston, or piston rings
- Im proper i nstallation of piston ri ngs
- Scored or scratched piston or cyli nder wall
Excessive Noise
Cylinder head
- I ncorrect va lve adjustment
- Sticking valve or broken va lve sprin g
- Damaged or worn camshaft
- Loose or worn cam cha i n
- Worn o r damaged c a m chai n
- Worn or damaged cam cha i n tensioner
- Worn ca m sprocket teeth
Cyli nder, piston
- Worn cyli nder and piston
- Worn piston pin and piston pin hole
Rough Idle
•
Low cylinder compression
Piston Knocking
•
Worn cylinder, piston or piston ring
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Worn piston pin and piston pin hole
•
Worn connecting rod smal l end
Excessive Smoke
•
Worn, stuck, or broken piston ring
Abnormal Noise
•
Worn cyli n der and piston
8- 1