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[dan1612]

Hi All, what should be a good PSI value for a 1955 350 Bullet, just rebored, new piston etc. valves re-lapped. I would expect that I could more or less stand on the kickstarter on the compression stroke but getting a measly 45psi at best. decamp' valve seems to be OK,

[Davie Hall]

Before you start worrying about compression values , I would try a compression test on another engine. My compression tester failed after very little use and only read 70psi max

[Tim NZ]

Not run at all? Don't expect full pressure straight off. Rings dry or oiled?


Double check the tappet settings, in fact loosen them off and recheck compression. A thou or two actual clearance can make a substantial difference.


110psi is considered normal.

[dan1612]

So dry at the ,moment. This has not run yet since rebuild. I'm going to try your advice re: tappets as I had to adjust the exhaust side - it had loads of play, may have over done it, but I did check this already.
Thanks for the suggestions .... I'll report back tomorrow

[simon]

Did you open the throttle wide before you kicked it over? If it can't get a decent lung full it won't have a decent compression reading. Also completely agree that you need to give it a run before expecting a full reading.

[andy w]

Hi Dan, I have had a similar problem and posted on this site earlier this year.I was advised to use a compression tester but never got round to it.I did try adding some oil to the cylinder and checking the compression again,it felt better which pointed to leakage from the rings. I was also advised to just ride it and have done so this summer. I am still not happy with the compression when kicking over, also using a bit of oil and have some oil leakage at the oil filler cap. I am planning to take it apart this winter to check things.
I would be interested to here what you find with yours. Andy.