i bought an 86 IROC Z 28 that "suppossedly" had a rebuilt engine installed but, sat for at least 4 years. i got the car running again after an electrical nightmare (was converted from TPI to carburated) and noticed it would blow a cloud of white smoke at startup that smelled like oil. i was told it was my valve stem seals that were probably dried up so, i had them replaced.
my question is this: should the smoke go away instantaneously, now that the seals have been replaced? or will it take some time? i just drove it home from the shop and it did the same thing it was doing before

......please help and thanks in advance.

 

should been fixed and smoke free after the first start up if it were the valve seals and you replaced them correctly and that was the problem.

 

didn't wanna say it but, piston rings?

 

White smoke = coolant/water being burned off
bluish-tint = oil being burned
black = running rich

Like ede said, the valve seals would be an instantaneous fix. Maybe 1 or 2 startups to burn off any residual oil, but that's about it.

Make sure it really is a light blue shade of oil and not white. As indidicated above, they are 2 very different issues to deal with.