Oil in the Turbo charger

[mailand]

I have a 1978 930 rebuild with B&B headers and oil collection pan for the turbo.
The turbo is a refurbished original KKK 3LDZ. But when ever the car has been standing for a while oil leaks into the turbo! especially when the oil level in the oil tank is close to max. I have checked oil return pump and it looks ok. The oil leak seems to be related to amount of oil in the tank. I think the oil runs backward from the tank through oil return pump and are then pressed into the turbo. Could the oil pump be defect or is it something els? I do hope somebody can help me crack this problem

[lucittm]

Mailand,
Just to clarify, the oil leaks into the air side of the turbo or the exhaust side of the turbo? Or, are you saying it just leaks into the center section and then out into the collection pan after standing for awhile?

Thanks,
Mark

[Jim2]

I'd suspect you have the oil return line from the scavenge pump connected to the wrong fitting on the oil reservoir. There are two similar fittings near each other and one is capped off from the factory. The capped off fitting goes to the bottom of the tank. The other fitting has a tube which extends to the top of the tank, specifically so that oil does not drain back through the scavege pump and then fill up your turbo.

[mailand]

Originally Posted by Jim2

I'd suspect you have the oil return line from the scavenge pump connected to the wrong fitting on the oil reservoir. There are two similar fittings near each other and one is capped off from the factory. The capped off fitting goes to the bottom of the tank. The other fitting has a tube which extends to the top of the tank, specifically so that oil does not drain back through the scavege pump and then fill up your turbo.

Thank you for the answer Jim - it sound like a plausible cause of error. Do you know which of the fittings are normally capped off, right or left looking at the oil reservoir from the back side? the oil return line is currently fittet on the left one.

Regards Peter

[mailand]

Originally Posted by lucittm

Mailand,
Just to clarify, the oil leaks into the air side of the turbo or the exhaust side of the turbo? Or, are you saying it just leaks into the center section and then out into the collection pan after standing for awhile?

Thanks,
Mark

Hi Mark thank you for showing interest. The oil leaks into both the air and the exhaust side. The more oil in the oil reservoir the more oil in the turbo until the oil level in the oil reservoir reaches close to minimum on the oil stick.

Regards Peter

[Jim2]

One fitting is in front of the other. Loosen the line from the oil reservoir, if oil continues to drain from the resevoir, it's the wrong fitting. With the correct fitting, you will only see 1-2 oz of oil come out of the reservoir, but then no more. I won't be near my car until Tuesday to see which of the two it is. Perhaps someone else can chime in and advise which of the two fittings it is.

[CMax]

I'm a little new at this but it happens that I have a scavenge tank sitting here beside me. It's from an 89 but it may be the same. The oil from the turbo drains down a line into the lowest part of the tank. There is a line about the same size that exits the cylindrical portion of the tank almost at the top that is the breather. The oil return that goes to the scavenge pump exits from the top of the cylindrical portion of the tank. I also believe there is a small screen inside the tank that stop debris from being pulled into the scavenge pump which is accesible through the hex nut on the bottom of the tank. Chime in if I have been inaccurate with the post as I don't have any great expertise in this yet.

[Jim2]

CMax, we are trying to determine which fitting it is on the reservoir in the fender that the scavenge pump discharges to. I seem to recall it's the forward most fitting, and the rearwards fitting is capped off, perhaps you can have a look at your car and confirm.

[mailand]

Hi Jim, I had a look at the oil reservoir yesterday evening and oil line is currently fitted on the rearwards fitting and the forward is capped off - please look at the attached photo. I also added a photo of the oil scavenge reservoir at the turbo. This is not the original reservoir, I wondering if it has any influence on the oil draining that this reservoir has no airing as the original has? Sorry for all these questions this is my first Porsche……
Thank you for helping.
Peter

[Jim2]

Peter, I checked and you do have the line connected correctly. I guess the problem is elsewhere.

[mailand]

Thanks Jim - I will carry on fortunately I'll have the whole winter to short out this problem. Anyway If anybody else have an idea how to solve this problem please quote.
//Peter

[DailyDriven'88]

I came across this thread and thought I'd check out a 1986 930 that Ive got in my garage. This car has the scavenge line going to the forward fitting and the rearward has a hose connected to it that travels into the engine bay and to the breather. So both fittings have hoses, none capped off. Do these need switching?? Not meaning to hijack here just sharing what Im seeing...

[A930Rocket]

My thoughts are two different sizes and you couldn't swap them if you tried. It's been awhile since I looked though.

No advice on the oil in the turbo, but before you start next time, pull the drain can off below it to see if it's full of oil. You said you had the ball in the check valve?

[mailand]

Thanks A930Rocket. I just found this morning that the flow control ball in the banjo was missing. The ball is now in place but I haven't yet had the time to check if it works. I think this is the cause to all my troubles. I hope I can do some serious TURBO DRIVING this weekend without sending smoke signals - YES
Peter

[jryerson]

a shop that worked on my car never put the 9mm ball in the banjo after a sender replacement, it made the scavenge pump work harder as it caused cavitaion and destroyed my pump, check to see if the pump is working by taking the suction line off the turbo oil tank and put it in a container with oil

[mailand]

exact same error here I bought the car from a dealer in San Diego (Automotive Excellence) with a newly overhauled engine, apparently they forgot to put the ball in the banjo as well. I will check the scavenge pump.
Thanks Peter

[mailand]

...it rocks everything is working perfect after placing the 9 mm ball in the banjo. Scavenge pump is pumping perfectly no oil in the turbo...... i had lots of fun driving my car this weekend with out oil smoke....
Peter