Turbo Issues

Been trying since summer to get my 86 Daytona running. Seems like I have just had one issue after the next and a lot of bad luck. It all started with an idling issue which turned out to be a major vacuum problem. It overheated a few times, but didn't seem like it had done any damage to the head gasket. Got the vacuum problem resolved, car ran great but then started smoking after it ran for a while. Kept letting it idle but it didn't seem to overheat anymore - no water in the oil, and the coolant wasn't pressurizing. So I thought perhaps the turbo oil seal failed. Got a fresh rebuilt turbo, installed in it, car ran fine for about 20 minutes and started smoking again. Thinking that perhaps the head gasket had actually blown, I started taking it apart again until I pulled the intercooler piping from the turbo outlet and found a bunch of oil. I don't see how it could be anything else but the turbo unless it is sucking a lot of oil thru the PCV from the valve cover, but that doesn't seem to be a problem either. Is it possible to have too much oil going to the turbo?

I am totally stumped how to proceed from here. So some help would be most appreciated. Thanks.

If the turbo is leaking oil through the seal on the hot side, you'd probably be able to detect that by dropping the DP and letting it run for a brief time. It doesn't take a lot of oil to make a lot of smoke though.

Have you inspected the plugs to see if you're burning oil in the chamber? What do your valve stem seals and valve guides look like?

If you're pulling enough oil through a functional PCV setup, I would think massive blowby is the root cause. A leak down test would really help to determine where you stand. Even a basic compression test would point you in the right direction most likely.

It could also be the valve stem seals, but Cordes is right. See where you have oil build up and that will help determine if it's pre, during or post combustion. If you have the motor together, pull the valve cover to check the stem seals. I had that issue with a CSX I owned and almost didn't find it until one day I had the cover off and noticed that one of the seals was higher than the other.

Starting with a cold engine remove the valve cover oil filler cap and start the car. Time how long it takes to see smoke. Wait a day and perform the same test with the oil filler cap tightly in place. Time it again. Did it take longer, shorter or the same amount of time until you saw smoke?

Chris-TU

The cylinder head has a fresh rebuild. But I will pull the VC and check the seals and do a compression test. Last time I checked compression, it was good. There sure did seem to be a lot of oil on the compressor side for it to be coming thru the PCV. I will have to pull the lower hose at the bottom of my Intercooler to see if there is more oil in there.

If it's massive blow by, does that mean something to do with the rings? The engine has a pretty fresh rebuild. If it is rings, how can you tells which cylinder it is?

Chris - what does that test tell you based on how long it takes before it starts smoking?

Thanks for the responses.

Quote:

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Originally Posted by JohnnyLightning86

The cylinder head has a fresh rebuild. But I will pull the VC and check the seals and do a compression test. Last time I checked compression, it was good. There sure did seem to be a lot of oil on the compressor side for it to be coming thru the PCV. I will have to pull the lower hose at the bottom of my Intercooler to see if there is more oil in there.

If it's massive blow by, does that mean something to do with the rings? The engine has a pretty fresh rebuild. If it is rings, how can you tells which cylinder it is?

Chris - what does that test tell you based on how long it takes before it starts smoking?

Thanks for the responses.

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Oil usually gets past the turbo seals when there is pressure behind it. Removing the cap relieves the pneumatic pressure. Noting a time difference and/or smoke intensity between the test lets you know if blow by or the PCV system needs to be addressed. Checking spark plugs and administering a compression check as some have suggested will also provide some answers.

Chris-TU