The background... Its a stock motor EVO 9 with bolt ons that after the new turbo setup made about 400whp. The new turbo setup is a FP Red 84mm turbo in addition to a new FP direct from the pump oil feed line as suggested by FP.

The issue... for some reason the oil return line at the turbo seems to be spraying pressurized oil while in boost. Normal cruising and while at idle it is fine and does not leak or drip, but once It hits boost it starts to spray oil at the turbo to oil return line connection. We have sealed the return line three times with new gaskets, silicon rtv, and red thread locker and still have this pressurized leak. It is an external leak that does not drip or pour, but sprays while the car and only while the car is under boost or high load.

Possibly cause... It has been suggested that the issue may be the result of excessive crank case pressure caused by the increased oil pressure from the new oil feed line. We have not had a chance to test this yet.

The question... Do you guys have any input or think that maybe a simple breather / oil catch setup will cure this issue?

Input, suggestions and advice welcomed.

Thanks again,



EDIT: UPDATE AND FIX

 

I would recheck the new lines installed, it seems there might be some blockage from the return side causing this problem.Make sure the line as no chance of bending and lets just hope and pray that what ever gasket you used didnt make its way inside the oil passage and clogged it up.

 

Its the factory return line pulled off the mint original turbo. Old gasket was still in tact, now using a new gasket and lock tightend the bolts and still sprays oil at boost and no leak when out side of boost.

 

I don't know man...maybe you need a oil restrictor due to the bigger turbo??? maybe someone will be able to chime in soon.

 

The FP oil line kit comes with a inline oil filter that I thought also included the restricter but I'm not sure.

 

Did you personally install the oil return line, or does someone else install the line onto the turbo? I ask because the flange bolts that secure the return line to the center housing are a true ***** to install once the turbo is on the car. It would seem way easier to install the line onto the turbo BEFORE installing the turbo into the engine bay.

It is pretty easy to strip the threads in the center housing. I would remove the turbo and inspect and reinstall the return line on your workbench. Sometimes the threads in one or both bolt holes can become partially stripped. That is maybe there is only a couple good internal threads left in the bolt hole and the bolt although it grabs can rock back and forth or not seat fully.

 

Are you running a stock pcv system?

 

^ Yes, I am using a stock pcv system.


I did the turbo swap my self. I intitialy installed it with the return line already attached to the turbo but since the leak I have had to do the repairs from under the car.

I was looking for something more technical in an answer then a lose bolt but your right and I probably should just remove the setup and check the houseing and ensure that it is indeed bolting & sealing properly. It's just that this is by far not my first turbo swap on an evo and I have over 200 miles on this install and its just now becoming an issue. Just threw me for a loop with three fixes and its still giving me issues.

Not to mention... watering the grass with several quarts of AMS Oil now is not my favorite past time. Last I checked its blood blood blood that makes the green grass grow and not expensive zinc filed oil. /my_joke_of_the_day

 

Check this thread out man....i had the same problem but my turbo was smoking after a hard pull...and doing a few mods to the valve cover solved my problem....remeber the stock pcv system was only designed to handle 300 hp max....your pushing alot more air then a stock turbo now.

https://www.evolutionm.net/forums/ev...re-issues.html

 

Check this out a guy had the same issue as you.
http://www.dsmtalk.com/forums/showthread.php?t=112025

I may just try the double up gasket technique. Last night I completely left out the gasket and am using RTV's high temp gasket maker to see if that will work. I drove it to work this morning and checked it and it doesen't seem to be leaking, just burning off remenents. If the double gasket doesn't work I will try some left over oil pan sealer that mitsu uses for their gasketless pans.

Ronin, I have had a similar problem with the flanges on the stock return lines because SBR gets theirs from Dejon. I went through 3 lines before I broke down and go the one from FP.

 

Update...


The fix... Ok so I let the car sit for a week or two while I got some other stuff done. I got a new pvc valve and pulled mine and noticed it was stuck open. Put the old pvc I cleaned and new one on the air compresser and both leaked but the new one from auto zone leaked a great deal more so I used my old one that now is working properly. I also capped off the intake line to the valve cover and simply ran just a breather filter on the valve cover side. I then cleaned and resealed the return line for a forth time.

The result... My issue is fixed and I noticed a small increase in my boost I had lost some time around the area when this all had first started.

The over all issue... From what I can guess, a stuck pcv was pressurizing my valve cover which in result was pressurizing my crank.case and causing my odd return line leak while under boost.


Thanks for the help guys.