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Discussion Starter · #1 ·
Well I had done a compression test a while back to find that one cyl. was low. So I had thought it was valves and was gonna put a set of heads on. So I decided to do a leakdown test to see if it was the valves. The heads seem to be alright its the rings is what I'm thinking. The results of the leak down are

CYL. %of leakdown location of leak

1 20% ringblowby as indicated by air through dip stick

2 20% ringblowby

3 45% ring blowby

4 45% ring blowby

5 48% ring blowby

6 48% ring blowby

7 42% ring blowby

8 20% ring blowby


This 460 has about 30k since rebuilt but has had the living sh!t run out of it. It has been run really lean for emissions and I'm afraid that has killed the rings. It does burn oil only when wheelin though(as it will only smoke after long decents of no throttle app. and once the gas is applied it smokes for a while (2-3mins)then stops) The leakdown test has shown the 3, 4, 5, 6, 7 cyls are worn pretty good. Aren't they all suppose to be within 10% of each other? There was no "hiss" from air in the other cyls, or exhaust, or carb. So how do these #s look to all you engine experts?
 

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as i stated at 4 AM, your motor is looking bad.
how does the oil look/smell? is it gas contaminated? i suppose you dont have acess to a 5 gas anaylizer to tell how bad the oil is.

will it pass emssions now, or is it failing?
 

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Discussion Starter · #4 ·
It passes emissions after I lean it out a bit. The oil smells like gas but I was running it rich for the winter and I haven't drove it much (2 wheelin trips) this summer. I had the cylinders at tdc on compression stroke each time.


I have a builder ready to be built but no money so I think I'm gonna have to live with it.
 
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