JDeitz951

So, while I'm in there...

Frustrated with trying to replace one old brake resevoir hose this weekend, I decided to rip everything off the front of the engine to track down the source of all the oil coming from behind the belt covers.

(I replaced all the seals 2 years ago and had the turbo rebuilt)

All the shaft seals are perfectly dry (a miracle), but there is a dirty oil film at the front of the pan, maybe the pan gasket, possibly lower bal shaft housing. What fun.

But I also spotted a lot of oil on the turbo. The top and bottom oil connections are dry. But the back side of the cold housing is dripping with oil. Is there known source for oil to leak from this area? It is not the oil supply line or the o-rings. The cast iron housing is oil free as it the motor support. But the rear of the cold side is dripping with oil and it is dripping down in the alternator shroud and everything under there.

If there is not a known leak source on the back of the cold side housing (I'm calling Majestic tomorrow to find out), then I have a feeling it may be coming from the large hose that run from the cold outlet to the IC pipe. I get quite a bit of oil in the IC pipes and this hose is original (one of the few remaining), hard and mishapen. Maybe the oil mist is spraying out under boost (now up to 18 psi) back towards the turbo. That would be too simple, but who knows. I'll replace that hose anyway.

Comments are welcome.

B951S

Could be oil blow by. Oil coming out of the center section and into the cold side. It would be blown through the intercooler and give oily hard pipes, it could be collecting in the cold housing and dripping out the back.

JDeitz951

Yes, I have oily hard pipes. Oil blow by I understand, but I did not realize the cold side itself could leak. I'll have to see what Majestic thinks of that, since they rebuilt it less than 2 years ago. It will suck if I have to pull the turbo. I should just top the oil and shut the hood in the future.

Danno

There's a large seal between the backing-plate and the compressor housing that can leak. Also the turbo-centers can leak if a shaft-seal is bad..

kasturbo

Does it look like this???




This was after two days on my rebuilt Majestic turbo. What kind of turbo are you running?

JDeitz951

Stock 86 turbo, so K26/6. Your pic is of the hot side. The cold side is where mine leaks. What did Majectic do to resolve this? I'm just curious, since I'm way out of warranty.

kasturbo

They said the seals were fine, but rebuilt it again anyways. I don't have it back on yet, so I don't know if the problem is fixed yet. I'm also going to run a restrictor now as I think I had way to much pressure for the bb turbo. Your stock turbo shouldn't have the same problems.

JDeitz951

I think the source of the oil (some of it anyway) is the oil mist separator. I just ordered this to fix that:

http://www.lindseyracing.com/Merchan...e=BREATHERTANK

Anyone ever try one? Sounds like a smart addition to a turbo, considering the effect oil has on octane.

I am pretty sure my oil mist separator seals are OK (2 yrs old), but there is a ton on grungy oil in the metal pipe coming from the OMS to the j-boot. I ordered the seals anyway, but I am damn sure the crank case breather tank will eliminate one source of oil in my turbo. Hopefully it's the only one.

I also ordered the idle hose update, which will eliminate a bunch of stuff under the intake. Only 3 hoses and the idle stabilizer will remain.

I think I'm going to clean everything up good and put the belts and pulleys back on without the belt covers so I can see where the oil is coming from.

David Floyd

This is my attempt a working catch can

I had bought a Lindsey can several months ago and did not like the hot oil smell that was emitted from the filter and finding it's way inside the car, so I bought a Moroso valve cover/oil separator and installed on the Lindsey can and plumbed back into the intake system. My hope is to stop most of the oil and only let the vapor thur, plus allowing a vacuum in the crankcase.

I also took the top off of the stock separator and packed it with brass scrubbers, also packed the Lindsey can also.

JDeitz951

Hot oil, not a good smell. Like an oil leak onto the headers BTDT. Maybe it could be mounted in a fender like the charcoal canister. In any case, I have a sheet metal shop, maybe a heat shield is a good idea to keep it cooler. What are brass scrubbers?

Well, first to see if it cuts down on oil consumption and leaking from the turbo, then perfect it.

With this setup there is no vacuum draw on the crankcase, so maybe less oil is drawn out.

David Floyd

That is a Lindsey catch can, I just modified it after I got tired of the smell.

Remove your oil fill cap with the engine warm and take a whiff.

I also thought about using a hose and running the filter into the fender well.

Brass pot scrubbers, raid your kitchen.

I liked the idea of vacuum being draw on the crankcase. old hot rodder trick so I routed a line back into the intake, but very little oil should find it's way there now.

brad-cam

Deitz, what was the outcome of your "leaky cold side turbo" problem? I just discovered that I have exactly the same issue...

JDeitz951

The source of the oil is not a mysyery since I added the catch can. It must be blowing past the turbo oil seals. I stopped the external leak by tightening the "clocking" hex screws (10mm) that hold the circular plate to the back of the cold side housing. Each screw tightened about 1/8 of a turn and that did it. I still have a lot of oil in the intake. New turbo on wish list!

brad-cam

Thanks. I think I have high crankcase pressure due to a ring problem as I also have my front seal blowing out. I'll try to tighten the clocking screws too.