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Crawford AOS Puking Oil

3558 Views 14 Replies 8 Participants Last post by  orestes85
I'm using a Crawford AOS on a built longblock with a GTX3576 @26 psi. I'm noticing that the breather line was puking oil all over the place while at VIR. It's not routed back into the intake. After seeing the amount of oil that was coming out of it I'm happy that we were just venting it to atmosphere and NOT running it back into the motor. The second issue is now it's smoking a bit and smells like it's burning oil. No smoke in exhaust or from the oil cap and exhaust doesn't smell like it's burning oil. The only smell is coming from the breather part from the AOS. A compression and leakdown test are already on the menu. Anyone have any thoughts?
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If you're overloading a Crawford AOS, I'd venture you have too much blow by or you're throwing too much out of the heads in the corners. Any other oiling mods?
no other oiling mods right now, we're looking a possibly going with an element dry sump though.

It's very possible it was due to cornering since I haven't had any problems with it at the strip or on the street. My biggest concern is why I'm getting burning oil out of it now but nowhere else.
if nothing's wrong once you get your results, you might be at a point that you need a dual setup, catch can + aos. I'm curious where this is going, good luck.
The A/O separator is filling (oil spewing) or is it just vapor escaping?

If you're spewing oil, something isn't right with the plumbing somewhere. Double check, post pics and lets see if we see any issues. No point is spending thousands if it's a simple fix. If you're not running slicks, bracing/cage, etc... you're nowhere near needing a dry-sump.
there was oil all over the engine bay where the breather line was routed. Down in the splash guards and all over the CAI.
pics of routing?

Something is either plumbed incorrectly or something bad had happened.
i'll see if i have some photos, but the car is down at the shop right now.
To clarify, it's not spewing oil anymore but i am getting white smoke that smells like oil.
No smoke or oil smell in the exhaust so I don't think it's the turbo. If it -is- the rings then it's not a huge failure (not that it matters how bad they failed). The only smoke I get is from the AOS breather line. Nothing in the pan/exhaust. We're replacing the cam and crank sensors and hopefully that's the only issue and it'll go back to normal.
Also curious to see where this goes. Did you ever do a compression test?
Take the actual AOS off and clean it out with solvent. You can still get sludge inside of it from all of the crap it's catching. Something might be gunked up. It was recommended to me to do this after every racing session or at least every other oil change.
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I'll give that a shot and see if it still smells like burning oil from the breather.
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