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Excessive crank case pressure frustration

Posted By: PAINT IT BLACK

Excessive crank case pressure frustration - 10/15/12 01:58 AM

I was using a K&N crank case breather... Nothing internally to baffle oil. Fresh motor build. At idle, everything's ok. Driven in higher RPMs, oil sprays everywhere from that little breather. Huge Mess.

Did. This before and the builder went back through it because of oil loss. Not smoking much, just oil getting sucked up into the pcv valve and fed to the intake.

So here we are again. My thought is to use a baffled breather (and maybe even a catch can at the pcv valve?) or a crank case evac system like this to manage the blow by:

http://chucker54.stores.yahoo.net/morcranevsys.html

I understand the rings aren't yet seated on this new motor, but this is obviously unusual. If a leak down test shows nothing very telling, am I on the right track for managing the oil.. At least temporarily?

The build: 360 stroked to a 408. Eagle crank, H beam rods, forged pistons, aluminum heads, hydraulic roller cam 248/254 duration, 109 separation, roller rockers .600 lift, M1 intake, final compression is 10.5:1 - dyno'd great for the budget at 500hpp/520tq.

Just trying to figure out wtf is going on!!
Posted By: Anonymous

Re: Excessive crank case pressure frustration - 10/15/12 02:15 AM

Is the PCV valve working properly?

I've had one stick before, the engine built up crankcase pressure and blew oil out the dipstick tube!
Posted By: moparpollack

Re: Excessive crank case pressure frustration - 10/15/12 02:18 AM

Are there baffles in the valve covers? What type of driving? Drag race? auto cross?
Posted By: RapidRobert

Re: Excessive crank case pressure frustration - 10/15/12 02:27 AM

I would add some baffles to the valve covers or get baffled ones
Posted By: stumpy

Re: Excessive crank case pressure frustration - 10/15/12 03:07 AM

Just to be sure you have a breather in one valve cover and the pcv in the other.
Posted By: JohnRR

Re: Excessive crank case pressure frustration - 10/15/12 03:17 AM

Add me to the baffles crowd , without them you are going to have happen exactly what is happening , the factory didn't install them in the valve covers to keep a 50/50 weight bias ...
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/15/12 04:13 AM

The baffles are there. Street car with a strip attitude. Pcv is new, acted this way with the old pcv. Forgot to mention leaking rear main seal. Again, fresh build.
Posted By: 64Post

Re: Excessive crank case pressure frustration - 10/15/12 06:37 AM

Do you have engine breaking when coasting down in gear?
Posted By: 340SHORTY

Re: Excessive crank case pressure frustration - 10/15/12 07:16 AM

Excessive crankcase pressure is only cured by installing new rings. Evidently your rings are not broken in yet or they were improperly installed/broken. Anything you do is only a bandaid for a serious internal problem..
Posted By: Challenger 1

Re: Excessive crank case pressure frustration - 10/15/12 11:49 AM

Something is not hooked right if you have a proper baffle in the valve cover.
I ran some MT valve covers years ago without baffles and it did this. I bolted a good sized baffle in the valve cover with the PVC valve in it and it fixed my problem.

Either that or your motor is junk.

Rings should and will seat within minutes of the motor running. Sorry to hear about the rear main...
Posted By: bobs66440

Re: Excessive crank case pressure frustration - 10/15/12 01:55 PM

Quote:

Excessive crankcase pressure is only cured by installing new rings. Evidently your rings are not broken in yet or they were improperly installed/broken. Anything you do is only a bandaid for a serious internal problem..

Mine is a fresh rebuild and zero oil usage and no perceptable crankcase pressure. I would do a compression/leak down test.
Posted By: RapidRobert

Re: Excessive crank case pressure frustration - 10/15/12 02:11 PM

Here's a very interesting short read on ring breakin issues. "breakin secrets" at www.mototuneusa.com
Posted By: MoparforLife

Re: Excessive crank case pressure frustration - 10/15/12 02:36 PM

Remember to that you need a vent on each valve cover. Not just one.
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/15/12 03:03 PM

I have baffles on both. I guess the leak down will tell the story.... This motor has been. 2 builds, both failures.
Posted By: 340SHORTY

Re: Excessive crank case pressure frustration - 10/15/12 08:51 PM

Id be looking for a different machinist/builder for the 3rd go around..
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/15/12 11:36 PM

These guys turn out a lot of motors and are very reasonable to deal with. We'll figure it out & ill probably get my Bee's big block done for the hassle.
Posted By: lewtot184

Re: Excessive crank case pressure frustration - 10/16/12 12:56 AM

doing a leak down test is the easiest and probably the most informative course of action.
Posted By: Molloy

Re: Excessive crank case pressure frustration - 10/16/12 04:11 AM

I had that problem on my 496. It was the higher Rs that slung oil. It wasn't the rings because it did great on a leak down test. I thought it was the longer throws of the crank. Anyway, a pan evac system pretty much eliminated the problem.
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/16/12 09:31 AM

That's the thing. The last time this happened, before we tore it down again, it was only the high revs that did it and the leak down / compression was fine. I'm not using a windage tray, and I think that might help? But if the leak down is fine this time around, I'm going to explore other ways of getting this under control. I bought only the best parts (for what it is), and I trust my builder.
Posted By: 64Post

Re: Excessive crank case pressure frustration - 10/16/12 05:41 PM

I’ll ask again, if you take the car up to 4-5k rpm and let it coast down in gear do you get poor/good/very good engine breaking? Does your exhaust show any blue under engine breaking?
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/17/12 05:17 AM

Quote:

I’ll ask again, if you take the car up to 4-5k rpm and let it coast down in gear do you get poor/good/very good engine breaking? Does your exhaust show any blue under engine breaking?



Sorry I forgot to address your question. Honestly, I only took the car down the road once because it needs an alignment and the brake rotors still had paint overspray on them (bad braking ability). From what I remember, it seemed to have good engine braking... normal, I'd say, based on the memories of driving the car before all this BS. As far as the "blue exhaust".... I don't know.

Don at FBO told me today that I can't run an evac systen on a street car due to the mufflers and back pressure that would cause the nasty gases to feed back into the motor/oil and it would just ruin the oil prematurely. I already had an order with Mancini because the tech there told me it would fix my problem. Don gave me some tips and will be working with me to address my problems if the leak down test shows no problems. I'll let you guys know.

BTW here's the car that is giving me hell.

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Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/17/12 05:26 AM

This was a good day... wish I would have known there was a gremlin inside that orange box.

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Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/17/12 05:33 AM

The motor from hell. I am going to light myself on fire if I have to break this motor down and repaint it AGAIN.

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Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/17/12 05:35 AM

Who knows, maybe I'll get lucky and we'll find the problem before I get 3rd degree burns.

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Posted By: 340SHORTY

Re: Excessive crank case pressure frustration - 10/17/12 06:43 AM

Quote:

Who knows, maybe I'll get lucky and we'll find the problem before I get 3rd degree burns.



and maybe not..


sorry, I had to do it..
Posted By: 1_WILD_RT

Re: Excessive crank case pressure frustration - 10/17/12 08:35 AM

Quote:

Quote:

Who knows, maybe I'll get lucky and we'll find the problem before I get 3rd degree burns.



and maybe not..


sorry, I had to do it..



Hey, All I'm sayin' is turn on the camera, never know what you'll see on You Tube...
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/17/12 09:28 AM

No joke, but during all this I accidentally shorted my ECU, and I found the spare I couldn't find before today. So after I made my last post (insomniac), I went out & swapped the bad one out. I cranked the car - had the hood open - and watched/ heard/ felt a big explosion. My timing is way off. The backfire bulged both mufflers & actually dropped one off the head pipes! Well, there goes a couple hundred bucks for new high flow AAR-T/A mufflers. I hope that's all it hurt. I'm going to set the timing from scratch again. I never had it dialed in before because of other lingering issues (tach hook up, throttle cable bracket//spring problems and a very leaky power steering pump). But the timing was pretty close... or so I thought. I have parts on the way and the tach & pump issues are fixed.

Hopefully this is just a timing related/ ignition system issue.... Or a bad dream..... Builder is coming over in a few days. I won't crank it again until I have some supervision. I'm learning though, so that is at least good, right?
Posted By: bobs66440

Re: Excessive crank case pressure frustration - 10/17/12 12:55 PM

Quote:

I'm learning though, so that is at least good, right?

Yes! Knowledge saves money and aggravation! Unfortunately, learning can be expensive and aggravating as you know. Sorry for your troubles, definitely a nightmare, but you're in good company. Many of us have been through it before...more times than I can remember...

..you'll get it figured out though
Posted By: bonefish

Re: Excessive crank case pressure frustration - 10/17/12 03:33 PM

i dont care how much hassle your havin THAT SWEET CAR IS WORTH IT
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/17/12 08:16 PM

Thanks. It's the only thing keeping me going. The car is so close to being the 'ultimate' to me. Can't come cheap or easy.
Posted By: burdar

Re: Excessive crank case pressure frustration - 10/17/12 08:26 PM

I'm glad your still working on it....even after it nearly killed you. It's just an engine. The hard work is done.
Posted By: PAINT IT BLACK

Re: Excessive crank case pressure frustration - 10/18/12 04:04 AM

Quote:

I'm glad your still working on it....even after it nearly killed you. It's just an engine. The hard work is done.



ha... surprised you remember that. I think about it almost daily and its been a few years now. Lucky to be here.
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