Guys, this is getting old for me. I finally got a proper rebuild and got my turbo straightened and balanced. The shaft was helixed by about .005. I just got this thing back together yesterday evening and now, I'm smoking just as bad, if not, worse than before the rebuild. I'm just due for an oil change which will be happening by Friday. I only smoke when I step on the gas after idling for a minute. If I sit in a parking spot and rev it to about 2000 rpm, it billows a decent size plume. It's only when I rev it a little. Any ideas? I'm really about to lose my mind over this car.

 

My first thought would be a hairline crack. Low pressure it seeps through into the combustion chamber and gives you the plume. At higher revs the oil blows past the crack, at lower it seeps. I've had this happen twice on iron heads, once with coolant once with oil. But since you've done a rebuild it's time to think about things that aren't touched during the rebuild. If it's worse it's because you have better pressure in your channels through all rpm ranges... First off: are you sure WHAT you're burning? A video always helps!

 

Do a leak down test...

is the smoke white of blue? how does it smell?
Have you done you valve seals?

 

That was my thought.....compression test, leak down test, and valve stem seals

Also, if the head was off, are you sure the head was torqued properly (15 ft lbs, then 44 ft/lbs, THEN another 130 degrees with a torque angle gauge!) That additional 130 degrees is important, just as it is to NOT re-use the stretch-to-yield one time use head bolts.

 

The smoke is without a doubt oil. I know the smell anywhere and it's very obviously blue since it's so thick. No leak down test yet but I did run the compression. From Drivers side to passenger side, 150,165,165,165,160. I'd say that's pretty good for a beater like mine! I have not done valve seals yet. I checked the pcv to find it nice and plugged, basically a loaded freight train for a dipstick and a puddle on my valve cover, so I have a feeling that the crankcase pressure is exacerbating a valve stem seal issue. I checked the turbo when I had it apart for cracks, I cleaned it thoroughly and poked around inside the bearing housing since I already have a tiny wastegate fracture. Only problem I have now is the fact that I spent 40 on balancing the turbo and 40 for a decent rebuild kit and now have no money. Throwing parts isn't exactly the greatest income in the world. I mic'd the parts to make sure they were in spec also. No Chinese knock-offs either.

 

there is your problem right there.... Your PCV and Valve seals

 

Sorry, I was talking about a turbo rebuild. Thankfully I haven't needed the head off yet so I'd say I'm doing alright.

 

I thought you did a motor rebuild. I was about to say, those numbers are unacceptable for a rebuilt motor.

How many miles does the car have on it? How about the motor?

The first thing you need to do is tune the car up, before fixing things. Unless the turbo was blown, the PCV should have come first.

#1 is at the timing belt, #5 is at the distributor. So, flip your numbers to put them in order. That #1 is low, should be 156 min. Did you do the test with the motor hot or cold? Did you also do a wet test?

 

The test was done hot almost immediately after parking the car. I did the Turbo because it was wining and burning oil. There was sludge in the heatshield area and the shaft was bent by several thousandths in three directions. I got a proper balance performed so this is the last Turbo rebuild. The motor is a tic over 172k.

 

Sorry to see your compression numbers on the low end. I did my test at 205,000 and they were something like 174, 178, 179, 176, 174. My daughters S70 GLT were lower, between 156 and 172. I may have done it cold.

Stay on top of the oil changes, hopefully they won't get any worse.

 

My engine is the HPT which has an 8.5:1 ratio which SHOULD read around 170-180. The 165psi cylinders aren't so bad. Even the 160 is ok since it's reasonably close, 4% or so. That 150 is iffy. I will do a wet test when I have the time to do so. I'm hoping that if it is a major problem that it's only a valve and not the rings. It's about time I won the lottery to help pay for all this work.

 

Your thinking too much into this...

You pcv is clogged, you have original valve seals and a motor that im pretty sure is over 100k..

Those a fine numbers on a dry test, wet test you should be in the 170-180 range.
If you dont do you pcv soon you will end up with a lot more problems.

as of now your probably getting blow by because of the pressure..

have you pulled the plugs to see which ones are caked with oil?

 

The book says that compression between 156 - 186 is within spec. So the only low # is the 150 number. As mentioned above a few times, get the car serviced, PCV replaced before you cause more problems. Having the turbo rebuilt as you seen was not the source of your smoking. Also, I doubt you are having much smoke from piston blow by. 19 Times of 20 low compression numbers are due to piston wear. Valve leakage usually results in a burnt valve in short order.

There are several post that proclaim how much smoother their car runs post the PCV replacement.

 

^this.....

You have compression dont worry just yet about low numbers... Do your PCV first otherwise your going to start popping out seals everywhere

 

The PCV will be done with my next paycheck. I'm really hoping I don't have any other issues. I kinda wish I'd done it when I had the manifold off. I'll get the pcv done and see how it works then and post an update.

 

i had the same thing. previous owner thought it was a HG so i paid 700 bucks. finally got it home and after a lil head scratching figured the pcv, fixed that and no smoke since

 

A few PCV tips....

1. The lower manifold bolts dont need to come all the way out
2. Make sure you clean out the Ports where the box connects to the block.
3. Make sure you clean your PTC
4. Make sure you have the bracket that holds down the hose on top of the manifold not under it..

The Block ports are more important than anything..

Keep in mind your still going to need to do the valve seals to stop the smoke 100%

 

here's pretty good pcv writeup:
PCV Replacement

 

I've already done the research for how to replace the pcv. I've just never thought it could cause so much smoke. Like I said, I wish I'd done it while I had the mani off boring it out. I had free access to it. Had the money too. I just wanted to push it off a little while to conserve the money. Actually doing the job is simple, laborious but simple. Oh well. I know what I'm doing with my days off in a week or so. As long as it fixes the issue, I'm happy. I'll do a wet compression test and post those number too. I can do that tomorrow.

 

PCV makes sense, that write up is thorough.

I thought by rebuild you meant engine rebuild, hence my hairline crack theory.

x2 on PCV/valve seals.

good luck and let us know what solves it for ya!