Rolf951

Hi guys, I was wondering if you all might could point me in the right direction....I have an 86 Turbo with a lindsey racing MAF. I've just recently got it running again after taking it to a friend's shop and having him reassemble it. The issue as the title states, is a huge amount of oil in the intake. So much that the car was running fine and then I put the clutch in to stop at a red light and the engine died with a puff of blue smoke coming out of the MAF and cone air filter. I was able to restart it and carefully drive it home. I'm trying to find the source of the oil and my suspicions are maybe bad turbo seals or maybe just bad vacuum line routing that's causing an issue with the crankcase pressure (vacuum). I don't know a lot about how the system works so I've been reading posts and trying to educate myself on venturi deletes and all that. From what I can see it doesn't have the venturis but I'll have to take everything apart and dig deeper. I do know that it has a dual port wastegate and manual boost controller in the cabin. I'm just wondering kinda where to start with this. Obviously I'm going to go through the vacuum system. Can someone easily explain the reason for the venturi's and with the MAF maybe I need to put them back on? I bought the car like this so I'm just having to work with what is there. What are the chances the turbo seals are bad? The car has about 120K miles and I'm not sure if anything has ever been done to the turbo. I'd love to know if maybe there is a way to check the seals. Thanks for taking the time to read. Any help would be greatly appreciated.

mytrplseven

Very strong possibility the AOS (Air Oil Separator) is either defective or needs the two rubber seals. Also check the security of the seal in the oil fill cap. If that's ok then it's likely the AOS. Bad part of that is that It's a complicated part to get to. Check Clark's Garage for a sample of what's involved in removing the AOS. Since in the process you'll have access to the turbo, I'd recommend removing it and have it rebuilt by a competent shop. I went through this process a couple of years back and Evergreen Turbos in Ocala, Florida did mine and it was a bit over $400. While I was in there I did a lot of other things that I had access to. All this started with a couple of bucks worth of AOS seals. Good luck with this.

Rolf951

Thanks for your reply! I did the AOS seals maybe 5 years ago but worth checking again. I could have gotten something not right when reinstalling it. I just took the intake plumbing and intercooler off. Oil in both the turbo inlet pipe and the pipe from the intake to the intercooler. There was more in the intake to intercooler pipe but still a good bit in the turbo pipe. The turbo fins are dry but I can tell they've seen oil by the dried oil film on them. I'm going to try and simplify the vacuum lines while I'm in there. Also no idea when the timing belt was done so have to do that too. It's gonna be a big job. Poor car. Everything I touch just crumbles from age and heat. I want to do the 07K swap at some point. Trying to gauge how much $ I want to dump into it until then. What's a good way to tell if the oil is being sucked/pulled into the intake from a vacuum line/AOS or if the turbo seals are leaking?

Most of the oil was in this pipe going from the intercooler to the intake manifold

Turbo

RKT951

AOS my similar setup oil in the charge system was heavy I thought turbo seals and then the AOS unloaded totally. After brand new one charge pipe system was clean.

Rolf951

Thanks for your reply! I'm hoping it's just the AOS and not the turbo!

Rolf951

So, I continued with the disassembly today and got the manifold off. It looks like the AOS might be the issue since there is a lot of oil leaking around it. Secondary to that will be sorting out all these hoses and vacuum lines. I had thought that the car had the venturis removed but I see at least one still there. I'll need to do some research to figure out what needs to stay and what doesn't. For those of you that have done this before, any suggestions? I'm looking at removing the venturis of course and maybe the cycling valve and the metal pipes.

Glue Guy

Diagrams can be found on the Lindsey Racing site for routing of those vacuum lines.

N2MY951

Following. Ive have a new to me 951 with some oil in the charge pipe too but mine car has been sitting for years.

Chapman951

LindseyRacing sells a nice Venturi delete kit. Suppose you could DIY also.

Blue and Red lines go to the intake manifold.

Laust sells a nice 5-port vacuum manifold to simplify the vacuum lines.

Black51

What year is the car?

Oddjob

951s can blow quite a bit of oil thru the intake normally, especially when driven hard. Not unusual to see some oil coating the intake system. Maybe more so if the oil level is at or over full.

I'm not sure what would be going on that would cause blue smoke (burned oil, exhaust?) to blow out thru the air filter.

With the AOS, not much going on in it, unlike some newer car systems. Not easily plugged. If the crank case is over pressurizing, it might push the oil dip stick up. If the AOS vent is plugged, it wouldn't blow oil into the intake. AOS o-ring seals leaking would cause some wet oil spots down the side of the block. Shouldn't cause any real problem with the engine performance.

Are you sure its oil that is causing the engine to run rough, stall? Maybe just a big vac leak? Can you tell if it feels like its running lean or rich?

Does the exhaust smoke on startup, or blowing smoke when running? If burning oil - Turbo seals, completely shot piston rings, valve seals and guides.

Did you try a compression test or leakdown?