what is causing blown turbo oil seals?

**Fissionx** · 02-22-2004, 09:17 PM

This is the second time ive blown them. 1st time i thought it was just old and worn, now i know something is wrong. I'll put up a pic of my oil retun later, when i get a change to take a pic, tho i have shown Jon C a pic of it before and i believe he said it looked alright. What elce could be causing this? Would oil flow be causing this? or maybe something elce like oil pressure? My 328 is diff than the other e36 motors. I have the E46 oil filter housing. Could i be having problems with my oil feed?
This really has me fustrated and i want to find out what the problem is before i put on the turbonetics ball-bearing turbo on. Right now i am on the mitsu 17c turbo.
The 17c turbo is oil and water cooled. Missing one of the banjo bolts, i didn't hook up the water lines, all of the other AA turbos are only oil cooled so i didn't think it would matter. Would this be causing it to blow seals?
thanks in advanced for the help.
-Dan.

**diegom6** · 02-22-2004, 10:21 PM

Originally posted by Fissionx
This is the second time ive blown them. 1st time i thought it was just old and worn, now i know something is wrong. I'll put up a pic of my oil retun later, when i get a change to take a pic, tho i have shown Jon C a pic of it before and i believe he said it looked alright. What elce could be causing this? Would oil flow be causing this? or maybe something elce like oil pressure? My 328 is diff than the other e36 motors. I have the E46 oil filter housing. Could i be having problems with my oil feed?
This really has me fustrated and i want to find out what the problem is before i put on the turbonetics ball-bearing turbo on. Right now i am on the mitsu 17c turbo.
The 17c turbo is oil and water cooled. Missing one of the banjo bolts, i didn't hook up the water lines, all of the other AA turbos are only oil cooled so i didn't think it would matter. Would this be causing it to blow seals?
thanks in advanced for the help.
-Dan.

First Off! Your setup is custom or is a kit?

Anyway , a guy who has the same system (custom project) as me 325is Turbo, had the same problem , he blew his seals in the turbo, what caused it? the oil pressure, he did a entire write up about it...he changed the turbo for another unit and from it, he restricted the oil press upcoming in the turbo.

He putted a oil gauge and was reading more than 30 PSI at wot or so..at idle was less of corse...then he added a copper fitting of 1/8 ( just from the oil sender , not all the entire line if not werent enough oil flow)to restric the overflow or press and then was reading about 5-9 PSI in idle and 18 or so at wot...

He learned that the turbos needs a bunch of oil not underpressured in oil, I did the same before starting the car but I added a regulable valve and seted it at 6 PSI in idle and 20 PSI at max in wot, no have problem since...and he niether...

**NickG** · 02-22-2004, 10:46 PM

Sounds like you have too much oil pressure getting to the turbo. Either the oil supply line that you're running is incorrect, or the feed from your non-stock oil housing is providing too much pressure.

Plumb an oil pressure gauge at the inlet of the turbo's oil fitting to see what's really going on.

**Drifto** · 02-23-2004, 10:03 AM

Modern turbos do not have "seals" that can blow out. That is a common misconception. They use piston rings to control oil leakage. This is known as a dynamic seal. The gap of the ring is oriented up or towards the oil feed. There is one for the compressor side and one for the turbine side. These cannot be blown out like a rubber seal. Most problems are resulting from improper drainage. This causes the oil level in the bearing housing to rise high enough that it gets past the gap in the piston ring. This is why it's not a good idea to rotate the turbo center section more than a few degrees past straight up and down(oil feed up, oil drain down). The compressor side has a much tighter tolerance than the turbine side which is why oil comes out the exhaust more freely than the intake side when a drainage problem occurrs. I've found that if the drain is ideal, no restriction in the oil line is needed. I've always run turbos a full mechanical pressure and never had any problem with smoke. That being said, oil drainage on a BMW is a big problem, and solutions such as restrictors in the lines will help this problem but may not cure it. I'm probably going to have to use a pump becuase the t-netics manifold puts the turbo very low and I have almost no slope to my return.

**///3oris** · 02-23-2004, 12:26 PM

Drifto, you're saying oil pressure does NOT affect anything? Very interesting... where did you get your information from?

As to Fissionx, did you drive your car hard, or was this during idle? Are you sure it's oil from the center section? Did you properly prime the oil? Did you let it break in?

Boris

**Fissionx** · 02-23-2004, 04:30 PM

Both times were after i was driving somewhat hard. I notice it upon startup after that, 1st time car set over night, 2nd time car set for 3 hrs or so. Went to start it up and find it smoking.
What do you mean from the center section? Bearing Housing? Last time when i took the turbo apart there was oil all in the turbine housing, compressor, downpipe, lower ic pipe.
I am using 10w-30, what prime the oil and break in? Both times seals have blown in under 2 weeks during which the car was occasionally driven, so w/e the problem is its obviously very harsh.
Oil feed line and fitting for the filter housing are both from AA.

**///3oris** · 02-23-2004, 05:32 PM

You have to prime the oil the first time you turn on the car... otherwise you're runing the turbo without any lubriciation..

Another thing is that during cold-start your oil pressure goes up to ~59psi although the turbo isn't spinning fast... wonder if that has to do with anything?

Are you sure you have ALL of AA's parts? Are your turbo's new? Have you checked for play? Do you know if maybe something got overheated? Who's tuning are you running?

Sorry if I'm not helping at all...

Boris

EDIT: Who built your turbo's? Same place both times? Do you trust them?

**Fissionx** · 02-23-2004, 06:23 PM

Performance Techniques http://64.225.76.178/main.htm rebuilt the 17c the first time. Pablo and Joh C recomended them. They have rebuilt it the first time, i haven't taken it off yet since they blew again.
I am not familar with priming the turbo. Oil will rise up the return line initally a little bit into the bearing housing, then when first started i assumed the oil feed would get the oil in there quick, and any air trapped there would work itself out. The AA install directions don't say anything about priming, i assumed nothing of it.
Right now its the normal AA stg1 gen 1 17c mitsu turbo, i have the turbonetics t3/t4 in the mail.

I think i'll take the expert's advice and get myself an oil pressure gauge. I believe that or maybe oil return placement is to blame.

None of the other AA kits use oil restrictors? Normal oil pressure at WOT is like 50 psi correct? This goes through the other AA turbos and i never hear of this happening. Why only on my car?

**Drifto** · 02-23-2004, 10:05 PM

Boris, I'm saying that high oil pressure may be a problem with a poor drain, but on the whole, oil pressure does not cause the smoking. I worked a t turbo shop building turbos and kits for 3 or so years so I've seen this sort of thing first hand.

**Jasonb1971** · 02-23-2004, 11:13 PM

Drifto... you have some interesting information regarding how oil could leak past the ring seals.
My AA stage1 gen1 turbo also leaks oil into the IC piping, though not enough to make the motor smoke, it still bugs me.

To solve the problem I spoke with a turbo-guy and he said before I rebuild the turbo I should check the drainage, just like you suggested. Sure enough my drain line was kinked so I had a steel braided line made; that definetely helped slow the leak significantly, but not stop it.
My unit is mounted about 45degrees off center (notice second pic) which I'm sure doesn't help for the reason you suggested, the gap in the ring seals is apparently oriented straight up.

Also since the unit is mounted so low I have noticed that my crankcase oil level is critical, too much and it will leak like crazy into the IC piping. I make sure no more than 7.5 qts goes into the crankcase after oil changes.

Having said all of this, I still wonder how I can definitively determine if my turbo needs rebuilt or is this a problem I just have to live with, or do I need a scavenger-type oil pump like you spoke of?

My unit is a Mitsibishi but it came from AA with the numbers ground off some I'm not sure exactly what it is.
Any feedback from these pics?

Thanks
Barker

See the oil collecting around the orange part of the downpipe? Also the center section of the turbo is wet with oil but I think that is from either the supply or drain line or both. Where would I get a gasket for that drain line fitting?

See how it's rotated about 45 degrees?

**armedM3** · 02-24-2004, 12:48 AM

I wouldnt think that it would be your oil pressure. Coming from hondas i would have 75-80 psi on cold starts and WOT. I would think that your oil return is not flowing.
-Alex

**Drifto** · 02-24-2004, 09:06 AM

You can get a gasket for the drain from any turbo shop. Tell them you need a gasket for a td06-20g. In my opinion the center section of the turbo is at too great an angle. If you loosen the clamp that holds the turbine housing on, you should be able to rotate the turbo. To rotate the compressor side back into alignment, once you have rotated the turbo, compress snap ring and gently turn. However, Mitsubishi turbos commonly have dowels that locate the end housings in a certain orientation. If these have not been removed, they will have to be pulled out so that the center section can be rotated. The turbo will have to be removed to do this. If you have to remove the whole unit, simply remove the clamp that holds the turbine housing on to the center section (exhaust side) and pull turbo out. You should be holding the turbo minus only the turbine housing. Then you can proceed. IF YOU ARE NOT EXTREMELY CAREFUL, MAKING SURE NOT TO "COCK" THE END HOUSINGS WHEN DOING THIS, YOU WILL DAMAGE BOTH COMPRESSOR AND TURBINE WHEELS.

**Jasonb1971** · 02-24-2004, 09:40 AM

Thanks drifto. It sounds like if I'm going to pull go through the trouble of rotating the unit then I might as well pull it out so I can then inspect shaft endplay or see any other damage that might be causing the leakage as well? What do you think?

Barker

**got psi** · 02-24-2004, 11:00 AM

If your car has an excessive amount of blowby it will pressureize the crankcase ,therefor pushing oil out the seal. Look at other symptoms if you still keep having oil problems. Not saying it's not the seal ,but us F I guys are harder on the bottom end, I don't care what anybody says. Just 1 more thing to take into concideration. J.T.

**Fissionx** · 02-24-2004, 05:54 PM

Here are a bunch of pics of the oil return. Does this look to be problematic?

.

**///3oris** · 02-24-2004, 06:03 PM

Ok, this may be irrelavant, but is the drain that you have into the pan exactly where AA had recommend you put it? Reason I ask is that there are internal baffles in the oil pan... not sure if anything is in the way there. Also, I usually see turbo's plumb the oil on the other side of the oil drain bolt.

But like I said, this may not matter...

Boris

P.S. Who drilled the hole in your oil pan? Did they drop the pan to do it?

**Fissionx** · 02-24-2004, 06:12 PM

No i do all the work myself. That is where AA says to put it and thats where ive seen other E36s tapped. No i didn't drop the oil pan, i used alot of grease and left oil in there when i tapped it. Flushed it with about 20 quarts total of some thick oil ($1 a quart). Im pretty sure they are allways on that side.