Blowin smoke

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seddy
Mariana
Posts: 48
Joined: Wed Mar 31, 2004 11:10 am
Location: Columbus OH (please save me)

Blowin smoke

Post by seddy »

I did a rebuild on the 77 900ss, but got a tank full of what seemed to be a mix of gas and deisel (500 miles into the run in), needless to say the rings didnt seat. I have rebuilt the top end(honed new rings), but I still have a smokey front cylnder, the plug isnt fowling, the cylnder looks clean, and it doesnt smoke straight away. It takes about a minute befor it starts, and then it smokes for a while then stops.

My guess is oil is leaking into the exhaust, and doesnt cause smoke till its hot, which would mean the exhaust valve O ring?.

Anybody like to second guess my guess?

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Colin Linz
Diana
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Joined: Fri Jun 18, 2004 6:16 pm
Location: Brisbane, Australia
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Post by Colin Linz »

My guess is valve stem seals or guide wear. On a vertical cylinder this will normally show on start up, as the oil can leak down the valve stem after the engine is stopped. In this case, a horizontal cylinder, if it blows smoke after idling or running around 2000 rpm for a while the intake manifold suction could be sucking the oil through the inlet valve stem and seal assembly.
Cheers
Colin Linz

seddy
Mariana
Posts: 48
Joined: Wed Mar 31, 2004 11:10 am
Location: Columbus OH (please save me)

Post by seddy »

Thanks Colin, guess I'll be taking the head of yet again.

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