smoke on starts

[gtihop]

I'm having problems with start up smoke. The engine was re-ringed and had new valve seals and valves ground about 5000 miles ago. At that time all the ring clearances and gaps were in spec. Recent compression and leak down tests show 185-190 compression on warm engine, leakdown at 4% on 4 cyls, and 5% on the other two. It does not burn any oil while running, decelerating, accelerating, etc. Just a good puff at startup pretty well all times. Any ideas if the valve guides are bad or the alusil re-ring went bad? It's a 1983 3.0 SC that had 75k miles on it, rebuilt due to oil leaks and broken studs.

[Dennis Kalma]

I think that most 911's give a puff on start up....mine does from time to time. Biggest contributor is how you drove it just before you shut it down, seems like a bit of idle or at least low rpm seems to minimize the puff, if I go screaming into the parking lot and shut it down, pretty well guaranteed to do the smoke trick....

I think if your consumption is fine (meaning low) then I would not worry.....the figures look fine to me....

Dennis

[47silver]

I changed the oil from castrol to brad penn racing on saturday....mine has not smoked at start up since. A coincidence? I dont know, but check out the "ultimate oil" thread on the 911 bbs.

gary