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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
Took the front head off just to be thorough and no sign of anything suspicious, the seal didn't look like anything had blown through. When I rebuilt the motor I tried to tune it myself but I'm starting to think I did not do a sufficient job. there was a little bit of fluid sitting in the port of the intake valve when I pulled off the intake manifold. I think I have two issues.
1) The front exhaust manifold was loose which caused the leak
2) Bad Tune, I think the motor has been running super rich which has resulted in excess carbon and unburned fuel.
Pics of the valve and piston (The scratches on the piston are from me, dropped a small washer down the spark plug hole and had to fish it out with a screwdriver I magnetized..)
snip front head underside
snip Front piston at TDC
I think I'm gonna put it all back together, verify torques then take it to a shop to tune since I did a bad job. Maybe also lean out the Mikuni carb?
It wouldn't surprise me that you are running too much fuel and too much timing.. I suspect that you'll need to find someone that has built a similar motor.. Not sure where you got the build parts from but I'd think that Hammer Performance should be able to suggest timing and jetting.
Since the head is off, I'd replace the valve seal.. Check clearance on the valve stem.
Last edited by Max Headflow; May 22, 2023 at 02:17 PM.
I had all my work done by NRHS but I just discovered they closed shop back in 2020 (I was living in Japan the last 2.5 years) Anyone know of a good machine shop in the San Diego, Ca area? I think it's worth having the heads looked at by a pro?
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