Re: Where Do I Begin?
Posted by
RodneyCB750K1979 on
Dec 09, 2012; 6:39am
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/Where-Do-I-Begin-tp4033031p4033322.html
Thanks for everyone's advise. I did a pressure test and discovered air passing through #1 exhaust valves. I also picked up some air noise inside the crankcase which I believe indicates some leakage past the piston rings. I removed the cylinder head today and discovered the top of #1 piston and the head chamber looked like they were peened severely. This affected the valve seat area. I could think of three likely causes: predetonation, overheating, or a loose piece of metal bouncing around. The cylinder bore appeared smooth with no nicks or scratches. The #1 piston compression ring does not move inside gland and the piston has some distortion. Can I replace one piston only or do they need to be replaced as a set? Can the head be repaired?

