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Shift_Mike
10-14-2006, 09:06 PM
yes i think i may be pressurizing my crank case. For a while when i give my car substantial amounts of boost (over 10 psi for the most part) i will get quite a bit of oil in my catch can. When running high boost for an extended period of time like a 1st all the way through a 4 gear pull i have blown my dipstick stick out before while boosting around 18psi.

now at first i was worried about this because i thought it was blow by.

so i did the normal thing, i did a compression test and it was normal 150 in all cylinders. Then i did a leakdown test. And i had 0 leakage in all 4 cylinders.

So now i was puzzled.

But today. I have no clue why but it just hit me that maybe i have a valve oil seal problem? Anyone experience a problem like this before? If anyone has any input i think i might just replace them this next weekend im sure my work could order me some in.

The car does not smoke out the exhuast on start up or while idling though. Or even cruising for that matter only when i give her some boost will i see some smoke and some oil in the catch can.
And yes the turbo is good and my pcv system is working properly. And the catch can as well is installed correctly.

jakerps13
10-14-2006, 10:13 PM
It would help if you could shoot a pic of your setup. I'm more interested in how you rounted the catch can.

Don't forget, in stock form, one part of the "T" from the valve cover goes between the MAF and turbo. I'd highly recommend to run it this way again. Also gives free horsepower by reducing/deleting windage in the crankcase.

Not that it matters a whole hell of a lot, but this is an SR right?

Shift_Mike
10-14-2006, 10:45 PM
oh, im sorry i forgot to add that. This is an s13 redtop engine.

i unfortuanantly dont have pics at this time. And dont know where the camera is, but i can tell you how i have it set up.

i have 1 piece of 5/8 hose that goes from the breather in the crankcase up to the back side of the T on the valve cover. Then I have another piece of 5/8 hose that goes from the front side of the valve cover to the catch can. Then Catch also has a small breather filter on it.

Im not running a hose back into the intake pipe in between the maf and the turbo inlet like the stock set up. I am running an upgraded turbo and have heard of times at high engine load when your turbine is really spinning it can pull a suction hard enough to suck oil out of the crank case and into the catch can. Thats why im not running this set up.

forcefedS13
10-14-2006, 11:03 PM
oh, im sorry i forgot to add that. This is an s13 redtop engine.

i unfortuanantly dont have pics at this time. And dont know where the camera is, but i can tell you how i have it set up.

i have 1 piece of 5/8 hose that goes from the breather in the crankcase up to the back side of the T on the valve cover. Then I have another piece of 5/8 hose that goes from the front side of the valve cover to the catch can. Then Catch also has a small breather filter on it.

Im not running a hose back into the intake pipe in between the maf and the turbo inlet like the stock set up. I am running an upgraded turbo and have heard of times at high engine load when your turbine is really spinning it can pull a suction hard enough to suck oil out of the crank case and into the catch can. Thats why im not running this set up.

ive heard this too. Alot of modded Sr's dont run the hose between the MAFS and turbo for this reason. Just what ive heard from so many people.

jakerps13
10-14-2006, 11:08 PM
If you have a baffled catch can, where you have the breather, you can run another 5/8 hose to the inlet of the turbo. Key here is baffled catch can not the cheap ebay knock offs. Also, the stock lines that run from the T to the inlet have a brass insert to prevent oil from just draining into the inlet.

I am not disagreeing with any of you, because if you have it setup wrong you can pull oil in the inlet as you previously said.

Try running another 5/8 hose and just venting it to the ground instead of a restrictive filter.

Shift_Mike
10-14-2006, 11:13 PM
i have a greddy catch can.

im not worried about how my catch can is set up i know its not causing the problem.

I had my car with the catch can set up the same way for a while before i started getting oil in it.

s14rhd
10-15-2006, 02:06 AM
Rings are probably shot, can get perfect compression test readings and still have poor oil control rings. SR's do not blowby oil when heathly. Most people never get a drop.

jakerps13
10-15-2006, 02:45 AM
No piston rings completely seal. Yes, I agree with you s14rhd that the biggest positive crankcase issue is rings. I'm sure the rings aren't as good as they used to be, especially if you just started turning up the boost.

Just because you have a filter on the catch can, they still can get plugged and need to be cleaned/replaced.

It seems like it's a far cry for valve stem seals. Vent the catch can as I recommended, put a new o-ring on the dipstick and rip it.

Shift_Mike
10-15-2006, 07:50 AM
still possible to get 0 leak down with bad rings?

green91
10-15-2006, 08:54 AM
Yes because you wont show leakdown past the compression rings but the oil oil control rings can allow oil past them.

Shift_Mike
10-15-2006, 10:23 AM
well ****...

Ok well being as vavle seals are easier and cheaper to do first im gonna throw some on. At least i wont have to pull the head or the sr out yet. If that wont fix it i guess its time for new rings.

I have CP 86.5mm 9.0:1 CR pistons in there right now. Would a hone and a re ring be sufficient? i would hope it would.

jakerps13
10-15-2006, 02:31 PM
I have CP 86.5mm 9.0:1 CR pistons in there right now. Would a hone and a re ring be sufficient? i would hope it would.

More than likey be just fine.

steve shadows
10-16-2006, 06:50 PM
all motors have a certain degree of blow by

what is safe and what is unhealhty blow-by differs from engine to engine.

Turbo motors typically have more crank case pressure and blow past the rings than other types of engines. The sr20det off a front clip will have a lot under high boost, I know because ive pushed upwards of 26 psi through the stockers and they like to puke oil out of the breather if its not circ'ed intot he turbo inlet as others have stated.

NOW if its smoking out of the crank case vent that means your rings are bad and if its really smoking or shooting out drops of oil off load then you prolly toasted some ring lands.

I know from personal expericne.

hope that helps a bit

Shift_Mike
10-16-2006, 07:25 PM
well i remember for a while maybe 6-8 months after my rebuild i had nothing in my catch can whatsoever. So i know what a healthy SR should have for blow by and I hardly had anything in there. Now im getting quite a bit.

I gave CP a call today and I bought a set of rings for 105 bucks. Im gonna pull out the engine and get it rehoned, probably get the block decked and head machined just to make sure my HG seals again. You guys reuse your cometics or get new ones?

This will give me a good chance to re paint my car too now that i will have the engine out. kinda cool lol.