Blue smoke after idle

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Just to give a quick run down, 85 Buick Skylark FWD 2.5 TBI 95k original miles. It is giving a cloud of blue smoke after sitting at a red light for a while and then pulling away. Sometimes it doesn't at all but most of the time it does. Never smokes while going, not even at full throttle or redline, just after a period of idle time.
Quick history on it, I owned it years ago and sold it to a friend. It broke down on him and sat in his yard for 7 years untouched. I got it back, did a MMO soak before attempting to turn it over. It started right up with no issues after replacing the little piece of rubber hose connecting the fuel pump to the pickup. Ran fine even on the gas that was in it. Didn't smoke or anything and drove well from the get go. It always used to ping pretty bad but stopped pinging after getting the valve seals and PCV valve done. Compression was perfect on 3 cylinders and 10 PSI less on 1 but well within spec. Been about 2k miles since resurrecting it and it is starting to blow the blue smoke after pulling away from a light. Never even a puff when cold starting and doesn't smoke blue even at idle till it gets to full temp.
Most facts suggest valve seals but they were just done so I would think they haven't gone bad yet. Has QS Defy 5w30 in it currently. Should I try anything or is it just time to take it apart and rebuild? Not sure if I should try a catch can, swapping out the PCV again in case it is bad or any of the bottled remedies. It runs,drives,starts and idles perfectly. Thanks in advance for any advice.
 
I'd say worn or stuck rings actually. Stem seals tend to puff when starting the car after sitting. Rings tend to smoke after engine is warm and at idle....traffic jam etc.

These engines are notorious for both issues. It harms nothing...
 
Car is 30 years old..she needs to smoke a little. Regardless of that blue smoke is oil entering the combustion chamber. I would read your plugs to see what is going on in which cylinder. Could be a cracked ring, could be a valve stem seal. Make sure your pvc is pulling good vacuum and that is working properly.

Maxlife 5w30 may or may not help you out on the seals..there are testimonies on this forum that it has worked in the past.
 
Funny thing is it didn't smoke before the valve seals were done. I might try another round of HM oil. It actually isn't low at all so it doesn't seem to be using much but kind of embarassing. Then again the car is pretty ugly so it kinda goes with it. Might try a heavier oil to see if it makes any difference. The owner's manual allows 15w40 so I may try some 10w40 Maxlife that I have laying around to see if anything changes.
 
Originally Posted By: Doublehaul
I'd say worn or stuck rings actually. Stem seals tend to puff when starting the car after sitting. Rings tend to smoke after engine is warm and at idle....traffic jam etc.

These engines are notorious for both issues. It harms nothing...

It actually drove much better for a few days for no reason so I wonder if it isn't the rings being stuck. I will probably just keep driving it and see what happens, maybe they will loosen up. If not, it was a free car, drives well enough to maybe tear into it at some point to get it fixed up. Gets good fuel economy too.
 
Its an X car,if that's the worst its doing,you are very lucky.Much better than 95% of the people who owned one.
 
Some folks thought small block valve stem seals are the same as Iron Duke valve stem seals. They may not be depending on year. Many people tried that. I wonder if this is the case.
 
They were Fel-pro valve seals and they were the proper ones. I actually got a full engine gasket kit BUT it was from Rockauto so I wonder how old the seals were. They looked fine but you never know. May have to give that a try again with some fresh seals. Only the intake valves got seals and all the valves got stem seals of course.
 
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