Did a boost leak test, valve cover leaks???

[DiamondStarM]

I did a boost leak test today and couldnt find much as far as leaks, so Im satisfied, but I pressurized the system a few times to be sure and on the last one I noticed some bubbling by the valve cover, I guess I need to replace the gasket, but has anyone else seen this before, seemed like a new one according to my previous searches. It was a extremely small bt of oil bubbling around the front left of the valve cover.

 

[oldman]

http://www.dsmtuners.com/forums/showthread.php?t=174682&highlight=boost+leaks

Read through the thread in detail and post back questions if you have any.

 

[DiamondStarM]

I have to wait till I can borrown a compressor again to do another boost leak test, but I did order all the valve cover gaskets from RRE and did a compression test in the mean time, I got 175 170 160 180, so I put the oil in cylinder three and it jumped to 210 so I guess the ring is bad. So if its possible that the ring and turbo seals are bad that could cause the boost leak to the valve cover? BTW I took off the PCV valve to make sure it works correctly and it does. Kinda confused here. The car only has 60k and never gets ragged on, why the premature ring failure?

 

[oldman]

If you're not blowing smoke and burning a lot of oil, you're probably fine. I was told by a dsmwiseman that when there's no oil pressure, it's possible to leak air through the turbo seal but I do think it's probably early sings of turbo problem. The key is whether the car is blowing smoke.

 

[nazthug]

ok i tried pressure testing again, this time straight into the tb elbow

at first, i hear a bunch of air escaping at parts of the valve cover gasket, so i unscrewed the oil cap and PFFFFFF all the air imediately came out of hte valve cover, instantly, all 10psi

Is air supposed to even go in the valve cover? WTF? Im worried now, whats going on? I didnt set up the engine in any specific order, but that should matter, even if the valves are open, they should be sealed into the valve cover, otherwise you would get all the oil into the engine burning

what is my problem? This sux if its not supposed to happen

and if it has something to do with the pcv valve, where is the pcv valve? I dont know where it is, i can cap cap it and see if still does it.

I hope i can fix this. This means that all my boost is leaking into the valve cover and back into the intake....and very badly, damn, my poor turbo, its workin so hard to get 18psi at the manifold. Shit.

 

[DiamondStarM]

The car never blows any smoke, a little has been burning off the turbo lately, but thats my own dumb fault. I just installed a B16G about 1-2k ago and reused the crush washers on the oil feed. I know it wasnt a good idea and I have some crush washers on the way with my other RRE goodies. Any other ways to check turbo seals? Thanks for all the help by the way.

 

[nazthug]

well i pulled the pcv and capped it, and it seemed to have fixed my valve cover baloon problem. If i blow into it, it still seals up, but i guess with more pressure, it opens up


also my biss valve was leaking(1st gen tb, plastic, i pulled my 2g one out, metal, and pluged it in) and that fixed it.

Had 1 tiny vacum line leak.

STILL>>>it wont hold ANY boost, within 10 seconds, my 8psi goes to 0!!!!!

Damnit, this is why my car isnt as fast as it should be...grrr...

So now i gotta wait till i can get an air compressor again to test it with more pressure, because with my little portable pump, it only gets about 8psi, and its not enough to actually hear a leak, i need like 20psi to hear the leak

Im kinda depressed, this sux, especially when i hear some people hold 25psi for 5 minutes...jeez

 

[oldman]

You're welcome. The link I gave you show you exactly how to eliminate the possibilities of a crank case/intake leak which includes the turbo seal, did you read it?

 

[DiamondStarM]

I read through the link you provided and did all three tests. I still had a leak after hooking up the boost leak tester to the LICP and after blocking off the PCV valve. I had previously done the wet compression test and my low cylinder(175-170-160-180) did jump up to about 210 when I added oil. So I guess the final conclusion is that the piston ring is causing the leak. My question is, is it necessary to have the engine at TDC when doing a boost leak test ti ensure all the valves are closed. Also as minimal of a leak as it is, is it safe to continue running this way? Thanks again.

 

[Black95TSIawd]

160 isnt a bad reading though.

 

[oldman]

I read through the link you provided and did all three tests. I still had a leak after hooking up the boost leak tester to the LICP and after blocking off the PCV valve. I had previously done the wet compression test and my low cylinder(175-170-160-180) did jump up to about 210 when I added oil. So I guess the final conclusion is that the piston ring is causing the leak. My question is, is it necessary to have the engine at TDC when doing a boost leak test ti ensure all the valves are closed. Also as minimal of a leak as it is, is it safe to continue running this way? Thanks again.

Where did the other posts came from? I suggest doing the compression test, both dry and wet, to double check again. If numbers don't change than I would do a leak down to be sure.

Yes TDC would be a good way to see if it's rings, valves seals or both. As far as whether it's safe to run in this condition, I can't answer because I don't know. I do know service limit is 30psi, the difference between dry and wet. Hopefully some one else will jump in and provide you some insights concerning bad rings and effects of running with them.

 

[oldman]

160 isnt a bad reading though.

Agreed, that's why I think the test should be repeated.

 

[johnk]

Service limit is 133 for compression

 

[DiamondStarM]

Its not even that its a huge leak, you cant feel it if you put your hand in front of it but if you plug it with your finger and let go 10 seconds later it lets out a little pressure. Maybe thats normal and that the whole reason for the pcv and breather valve anyway. I am under the assumption that it shouldnt get and pressure though, maybe Im just being paranoid. Ill do a dry and wet compression test again tommorrow ang post back my numbers.

 

[oldman]

One small capfull of oil is all you need.

 

[DiamondStarM]

I just finished doing the compression test again after a 15 mile drive from work, so it was good and warm. I got the same exact results as before (175-170-160-180) and cylinder 3 goes up substantially with a drop of oil. And to add fuel to the fire I picked up a nail on te way home. I guess next Ill try a boost leak test at TDC...after I go plug this stupid flat.