Possible causes of blue smoke

[turbosam6]

OK, still trying to find my problem. The car blows blue smoke at idle. Heres what I have: Brand new long block with GN1 aluminum heads. Car is mainly doing it at idle or very low speed. No problems under boost or moderate acceleration. Tried disconnecting the PCV, no help. Inlet pipe is clean. No oil out the exhaust side of turbo. Its done this since we put the new motor in. So far, the only possible causes I can see is either a vacuum leak on the valley side of the intake or valve guides. I have dyno'd the car, and theres no blowby, so I think the rings are OK. Its great under boost. Are there any other possible causes? Thanks

 

[turbosam6]

Forgot to mention that I pulled the plugs twice and they all looked the same.

 

[86brick]

My vote is valve guides.......

Do your GN1's have the sh!tty K-line valve guides?? If so I would replace those with good bronze valve guides..... Geno has posted about this before on here and that really sounds like the reason your car is smoking..... If only you would have stayed with your iron heads

 

[aketech]

I had the same thing happen

turned out to be a bad fuel injector it was spraying fuel all the time it was stuck open.

I though the head gasket was blown but when the new injetor was put in it went away.

 

[turbosam6]

Its oil, not fuel.

 

[turbosam6]

I pulled the plenum off and looked in the runners. There was some slight oil from my pcv, not much. I highly doubt its enough to smoke. I double checked the turbo, nice and tight, no oil in up pipe or down pipe. I will disconnect the pcv and try again. I had it disconnected before, and it smoked then too.

 

[azgn]

I vote for the turbo.............

 

[turbosam6]

Originally posted by azgn
I vote for the turbo.............

OK, how do I tell? It has no play in the shaft bearings, no oil in the up pipe at all, and worked 100% perfect before putting it on this motor. Short of putting another turbo on it, I see no way to totally eliminate it. And I don't have a spare turbo around to try. Wouldn't there be oil in the DP if it was the turbo?

 

[XXQUICK6XX]

How many miles on it now and what type rings are in it?

Steve


Also if you get a chance do a compression test dry and a few squirts of oil for a wet test and post results may have a cylinder that the rings ain't sealed in yet. Or as others have said the the guides or seals.

 

[BuickMike]

I've got the exact same problem with my motor, except for my motor has alot of miles on it. My compression is about 135 across the board. A leakdown test showed 8 to 10% only. The turbo is not leaking oil on the exhaust side. My runners are clean, so it's not the PVC. My plugs look great! I'm pretty sure that my issue is bad valve guides. You should really look into that even though your motor is new.

 

[turbosam6]

The motor has about 300 miles on it. All the plugs look the same. I don't think they are near fouled from the oil. Today I pulled the down pipe and found no oil anywhere at all. I spoke to John Craig this morning, and he said he bets its the turbo. I might try borrowing a spare turbo and running it, but I still don't think its the problem. Why would it go bad the exact moment I put it on a new motor? I would also think if 1 or 2 cylinders haven't sealed, the plugs would tell me.

 

[SloRegal]

I also think its the turbo. I had a freshly rebuilt motor in my car and it smoked at idle as u metion above. Checked the exact same things as u did, turbo, Dp, Up P, pcv, etc..., problem was the turbo, could not see oil in Dp but it was the exhaust side, had to pull the exhaust housing off to see the oil, just something for you to not over look. and it was a TE-45a brand new 0 miles on it.
SloRegal

 

[azgn]

prolly exhaust side leak, as mentioned....been there, done that