Mysterious oil leaks caused by boost?

[slowsixtyduece]

So Ive been trying to trace down oil leaks for the past year or so since I first fired up my 2276 turbo. There are no clear signs of oil leaks when idling or free revving the motor - it seems to begin spewing oil when the car is run hard through the gears with boost coming on heavy. Even when Im just cruising at highway speeds/higher rpms, the engine doesnt seem to spew much oil (a few droplets in engine compartment). Its just when I push it hard and the turbo is spooled (up to about 5.5k rpms) does it start pushing a lot of oil out.

Ive tried resealing the oil sending unit, galley plugs, crank trigger mounting bracket and so on. Ive replaced the distributor o-ring, cinched down alternator stand, etc. It is extremely difficult to tell where the leak is coming from. At times it looks like its from the around the distributor or oil pressure sending unit, but then there is oil on the other side of the motor too, on the tin down by the dipstick. Ive concluded that most signs point to the pulley, but its not a cheapo pulley - its a nice Berg unit installed according to their specs. I just dont get it...the engine mysteriously decides to leak oil from wherever it wants when its pushed hard.

Im wondering if perhaps I am experiencing some blow by and when boost is coming on, boosted air is making its way into the case and contributing to higher case pressures? If there was a decent amount of blow by, how much of a role could boost play in creating high case pressures? Would 8 lbs of boost with problematic ring sealing really contribute to oil pushing out every orifice when the motor is being wrung out, especially the crank pulley? Does this seem like blow by or some other issue?

Thinking it just needed "more room to breath" I decided to install a beefier breather setup. You can see the baffled catch can in the upper left corner in the image below. 1/2" tubing runs from both valve covers, stock fuel pump vent and oil filler stand all tie into catch can. Any oil collected in catch can runs back into case when motor is off. This, however, did not solve my mysterious oil leak issues:

IMG_0984-WEB.jpg

After some hard pulls, oil is all over bottom left tin under oil plug and on breast plate tin as seen below:

IMG_0986-WEB.jpg

While its a bit difficult to tell (look at the shiny vs. dull) oil is also all over the other side of the tin too, with a streak of oil on the breast tin:

IMG_0987-WEB.jpg

[Clonebug]

Are you positive you haven't had any detonation and cracked your pistons???

I had blow by with oil coming out and it was the pistons.
Put new P/C's om it and installed WI and it fixed the issue.

Detonation is a time bomb..............

[madmike]

Mine leaks too
Berg pulley also ,, total seal piston rings help
like an old "Harley"' if it has pushrod tubes it's gonna seep oil

[sideshow]

Venting the case is the normal fix, venting the heads normally increases leaks.

[Clonebug]

What are your ambient IAT's, boost IAT's and what timing are you running when under boost????

[bug66]

How much crank venting do you have?

[slowsixtyduece]

Thanks for all the responses so far. Answers to your questions/responses below....

Are you positive you haven't had any detonation and cracked your pistons???

I had blow by with oil coming out and it was the pistons.
Put new P/C's om it and installed WI and it fixed the issue.

Detonation is a time bomb..............

I am NOT positive I have not had any detonation. There have been a few times I have done a hard pull only to hear a faint "rattle" when under heavy boost, to which I immediately pulled my foot off the pedal. What was your blow by like? Lots of oil everywhere? And it damaged all your pistons or just a one? I am not opposed to tearing into the motor this winter, but I also dont want to do it needlessly.

Mine leaks too
Berg pulley also ,, total seal piston rings help
like an old "Harley"' if it has pushrod tubes it's gonna seep oil

Yours too!? How bad is it? Just from the pushrod tubes? Id expect it from the pushrod tubes and maybe spots like the valve covers, but not excessive amounts in the engine compartment from around the crank pulley, etc.

Venting the case is the normal fix, venting the heads normally increases leaks.

Tell me more...how does venting the heads increase leaks? Does it cause more pressure or something? Ive always vented my valve covers and this is the first time Ive had this huge of a problem...

What are your ambient IAT's, boost IAT's and what timing are you running when under boost????

Ambient IAT under boost is generally somewhere between 90-170* f range depending on how much boost and temp of the day. I live in the mountains so the air is cooler most of the time but we do see frequent 90-102* days in the summer, which is where the 170* f max comes in. If I recall correctly, I have never seen the temps under boost go much above 170* and they lower once boost is done. Without boost, the IAT is usually at least 10-25+ * f cooler.

Timing table WITHOUT boost is below...
RPM: Timing:
1000 13*
1250 15*
1500 18*
1750 21*
2000 23*
2250 25*
2500 29*
2750 30*
3000+ 32*

Under boost, the computer (SDS EFI) pulls approx 1-1.5 degrees of timing per pound of boost.

Im hoping to get water/meth injection in October to cool things down but if I have to tear it apart to fix, that may have to take a back seat. I have never had a hi-po VW engine leak this much in the engine bay on me. And it seems like its leaked from just about day one...I have done small things over the last year that have helped calm some of the oil leaks down, mainly the breather setup.

The only thing I can think of is that, after I first got the engine in the car, when I first went to start it, the EFI flooded the chambers with gas (bad ground and SDS is known to do this in this case). There was ALOT of fuel - much of it ended up in the oil and I changed it. Then we fired the motor up and broke it in. Maybe all that gas washed the cylinder walls clean of oil and somehow the rings gouged the walls, leaving me with a lot of blow by right out of the gates. The car seems to run pretty hard and doesnt seem to have any hiccups; I suppose a compression test or leakdown test might be the next order of business....

[slowsixtyduece]

How much crank venting do you have?

The only crank venting I currently have is the stock alternator stand with 1/2" hose running from it to the catch can, and 1/2" hose venting from the stock fuel pump location to the catch can.

[Clonebug]

When I had my blow by problems I had oil coming out of the dipstick, aluminum pulley,filler vent and anywhere else it could get out.
It was not too bad if I didn't boost over 6 lbs. but if I went to 13 I had oil everywhere.
I tried building a custom breather setup and venting the case and filler and draining to the 1/2 valve cover but it didn't really help.
When I read about CoryVdub's issue with his engine having blowby and finding cracked pistons and only replacing two of them....then having his engine blow to kingdom come......I pulled my buggy off the road immediately and replaced the P/C's. As soon as I started it with the new P/C's my blowby was gone.
I could never really find any cracks in the pistons but to this day with my detonation in check I have not had any issue with oil everywhere and my vent is just a hose off the stock filler with a Tee going down to a road draft tube and a V-8 style valve cover vent at the top of the hose even with the top of the fan shroud.
For the $185.00 for the P/C's and the $350. to have them swapped I have had peace of mind for over 3 years now.

Here is the page where I made the decision to pull the engine......

http://www.shoptalkforums.com/viewtopic ... start=1125


I don't want you to panic about all this but in my experience with detonation it is a real and present danger. I can hear my engine ping immediately due to being close enough to the engine but you might not be able to since it is in a bug.
I would hate to see you ruin a good case and internals especially if it is a stroker. You have a larger investment and it might be worth your while to check.
Like I said...Cory said his cracks were so minute that it looked like casting marks and I could not see anything with the naked eye.
As soon as I replaced the P/C's my blowby was gone.

This info is to allow you to make an informed decision.........It was only my experience and yours could be different.

[sideshow]

It beats me why when crankcase venting is needed...people aim for the heads. And neither will fix a bad piston/cylinder issue.

Venting the heads seem to promote them filling with oil, and that is why I don't do that.

[madmike]

Mine leaks from one of the head stud and the sump plate as far as I can tell
Jaycee tubes don't leak ,,,so far,,,

[petew]

You may not have piston issues. I had the ring gaps line up on Cyl 4. To diagnose it do a compression check. Pulling the oil cap off during idle will help you see blow by. If the air come out is smoky at all, you have blow by.

[seabeebuggy]

rings may be weak or toast. I had total seal rings go limp under 40 miles of boosting. Was too lean. Open the case up and let it breathe. blow by from boost will push that oil right out. I've seen a one way check valve added to a header at the collector to help pull pressure from the case. get your tune correct before boosting hard uses the best fuel 110 or so while tuning. Use a wideband to tune. Never read sparkplug on a turbo engine.

My 2006 sees 20 lbs and it is almost 10 years old now and no oil leaks. its not a daily driver by any means but it is the best VW engine I have ever had.

[eanico]

I agree with the below I think u need to vent that case. I am having a similar issue right now with my Turbo EFI 2054- it only leaks during boost and its actually from the breather box coming under pressure which I am starting to think its too small. I am using a small empi breather box. gona drill some holes on the lid to see if it lets it vent more. Honestly that's the only place is leaking.

I also agree on getting in tune tight- go with a buddy for a ride along and have him or her listen for detonation. Hope you resolved tho.

rings may be weak or toast. I had total seal rings go limp under 40 miles of boosting. Was too lean. Open the case up and let it breathe. blow by from boost will push that oil right out. I've seen a one way check valve added to a header at the collector to help pull pressure from the case. get your tune correct before boosting hard uses the best fuel 110 or so while tuning. Use a wideband to tune. Never read sparkplug on a turbo engine.

My 2006 sees 20 lbs and it is almost 10 years old now and no oil leaks. its not a daily driver by any means but it is the best VW engine I have ever had.

[bug66]

There is no thought needed on venting. You need a lot when boosting a motor. Preferably dry sump, vacuum pump or a lot of open area. Like 1,5" or more. Classic venting fail. Been there done that. Skip the useless oil filler and make/buy a tank with 1,5" in and a 1,5" air cleaner on it.