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oily NB intake manifold

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Old 01-10-2009, 03:42 PM
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Default oily NB intake manifold

I pulled the manifold today to replace part of the wire harness. While I had it off I noticed there was a bit more oil in there than I care to have. Nothing major, but there was some small puddles around the VICS stuff. Whats the best way to handle it? Vent the PVC to atmo? Catch can?
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Old 01-10-2009, 03:56 PM
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Catch Can on the PCV line couldnt hurt. When I pulled mine last week I had a lot of oil on #2 and #3. This was due to the location of the PCV port and it's pulling oil directly in. I don't like venting it to the atmosphere just due to the vapors/smoke it'll dump at idle.
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Old 01-10-2009, 04:11 PM
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I guess its off to e-bay for some Chinese made JDM bling
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Old 01-10-2009, 04:15 PM
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Originally Posted by Stealth97
I pulled the manifold today to replace part of the wire harness. While I had it off I noticed there was a bit more oil in there than I care to have. Nothing major, but there was some small puddles around the VICS stuff. Whats the best way to handle it? Vent the PVC to atmo? Catch can?
The PCV valve hose goes to the intake manifold and that's where the oil comes from. That and there's another hose on the valve cover that goes into the stock plastic crossover tube. When I pulled my intake manifold to install the nitrous foggers mine was NASTY inside. Full of oil buildup.

So I cleaned it all up perfectly. Then I built a DIY catch can and routed both the PCV and the breather to it using 3/8 hose. It stopped the oil problem in the intake manifold of course. But I would ALWAYS smell oil during or after a hard pull. And after a while, the little catch can was full of oil.

So I yet again set out to "fix" this, as I still wasn't happy. This time, it's back to the basics. I put a 8" piece of hose on the PCV valve it let it lay on the intake manifold with the end of the hose being a bit higher than the valve itself. Been this way for the last 5K miles and so far, no oil has came out and I don't smell oil after a hard run either.

As for the breather, I put a little filter on it. Not the best solution as the filter will get oily over time and begine to drip onto the exhaust manifold, where it burns off. I still never smell oil though... I'm planning to build a hard line that goes from the breather to the bottom of the car for it to vent down there. I guess I could put a catch can, but that takes up more space.

EDIT: Here's an idea for the breather. Build a hardline that hooks to it, but let it travel up some and then down to the ground. Think of an upside down pea trap. Rather than keeping the trap full of water and preventing air from moving, it keeps air moving, but prevents water (oil) from moving. I think I'll do this.
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