smokin'

[aoriii]

Small panic insued behind the wheel of my car last week when I started...I saw a good sized puff of blue/grey smoke from my exhaust. It doesn't do it all the time, but often enough to make me worry (about once every day or two).

Any ideas.

Thanks

 

[Rowdy1]

Guides

Could be the valve guides (seals) are wearing and some oil is seeping in to the cylinders after shut down. Then when you start it after sitting you have raw oil in them. Does it goe away after it warms up? If it did it while warm and running it "usually" means rings. There's a few tests you can do or have done to determine this. I'm sure one of our resident engine builders can be more specific.

 

[Mad-Mic]

thats pretty usual for a small block chevy after around 50k in miles. as long as it clears up after a few seconds your ok. like Rowdy said if it does it all the time and even on start ups that the motor is already warm i'd worry bout the valve guides like he suggests. if it only happens on cold starts its natural. mine does it also first start of the day. just a small puff of smoke then clears up with in a second or 2.

 

[WhalePirot]

New valve seals would probably solve the problem. The valve guides are metallic and the valves slide up and down through them, under the soft seals, which wipe the oil from the valve stems. These seals harden with age and allow oil to seep down into the combustion chamber; not a biggie, really.

While they can be changed w/o pulling the heads, I doubt the expense is worth the small amount of smoke you describe.

Hell, tell everyone you have a loose, hi-dollar racing engine which always burns some oil until up to temperature!
mike