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Old 02-18-2021, 07:37 PM   #31
AGELE55
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Join Date: Dec 2019
Location: NE Florida
Posts: 245
Default Re: Par car slow all the time

Quote:
Originally Posted by Tankercart View Post
gloved finger up the tail pipe.... lol nice. So I took the cylinder off and used the manual lochlin already posted for measuring and inspection. Sadly didn't find anything substantial to determine the cylinder is out of round. A little larger at the bottom of the cylinder but still well within limits. The ring gap is larger. The manual states .007-.023, and mine is .046.

I placed the cylinder on level surface and set the head on top with no gasket in-between. I do notice a very slight rocking one direction and not the other....

After re-examining the piston it's a little more worn than I thought. The skirt has some irregularities. I could buy a new one for 50 bucks and hope for the best.... But I talked to a guy today who told me he'd bore the next OS and mill the head ($70) if I got him the bigger piston and rings. All in $140 dollars. That's 20 dollars cheaper then the new cylinder, but I'd still have to clean all that carbon out of the exhaust port... what do you guys think? .020? worth it?

Side note: the piston connecting rod has some radical play. is that normal? I think there's a roller bearing in there, and probably shouldn't have slop, but it's a 30 year old engine.
For the $ difference, I’d probably go with a new cylinder. .046 is pretty loose. Not sure if it’s 65psi loose, but new parts at least remove all doubt.
So... define “radical play”. Or hopefully you meant radial play...lol
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