Catch can full?

biminiLX

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Cams are MMR Stage 3's. Vacuum is about -6 to -7 inches at idle. On decal in might run to -11.

More info. I had switched catch cans a few months back when the Sheby snake engraved was offered by I believe JLT. It catches much more than my old Watts unit, which only showed a small bit in the cup.
So, you’re having a catch can oil issue and recently changed catch cans?
But it shouldn’t be a part that causes this, just its catching more you may have missed before?
I’d also just swap the PCV and move on.
-J
 

Mojo88

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About 10 years ago, I replaced an Eaton roots style supercharger on a Pontiac Bonneveille SSei that I owned. The job itself was fairly straightforward, I didn't see how I could possibly mess anything up.

Well, I had used a fair bit of gasket sealant to make damn sure there wouldn't be any leaks of air or coolant, and I inadvertently used too much around the PCV outlet area, where it ended up plugging the PCV system. The engine responded by making these loud and regular chirping noises as the internal pressure kept trying to vent its way out. I finally figured out the mistake when I noticed the dipstick protruding out a few inches and I deduced that the PCV system was somehow plugged, so I took the S/C off and immediately saw the problem.

I only mention this because you say you had your S/C off and perhaps you somehow caused a restriction in the PCV flow, which is forcing the engine internal pressure to purge out wherever it can, taking the path of least resistance, which would be the catch can line.

Anyway, just a thought. Good luck.
 

merkyworks

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No No No Catch Cans are stupid and a Waste of Money.....lol

Catch cans do work and have merit when setup correctly. Biggest problem I see with a lot of systems is the length of travel the PCV air makes from valve cover to catch can to motor. It's to short on most systems and doesn't provide enough time to let the suspended oil drop out of the air.
 

mysticsvt

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Catch cans do work and have merit when setup correctly. Biggest problem I see with a lot of systems is the length of travel the PCV air makes from valve cover to catch can to motor. It's to short on most systems and doesn't provide enough time to let the suspended oil drop out of the air.
My apologies, my sarcasm was not clear enough as it should have been. Totally my fault.....I run them on my boosted Stang and defend them constantly. This is a case that they are rarely talked about and is a huge talking point in their favor. Usually however with the mild collection of oil/water the engine can consume it in the combustion cycle without damage but being that it does just that makes them a great idea. So a Catch Can does more good than bad.
 

70SCJ

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Id replace it and move on. Traditionally, the idea is that you remove from Valve Cover and shake it. If it
rattles its not concretely failed, but may not be operating optimally.

I'll replace and see if anything changes.

So, you’re having a catch can oil issue and recently changed catch cans?
But it shouldn’t be a part that causes this, just its catching more you may have missed before?
I’d also just swap the PCV and move on.-J

Correct the new catch can is catching much more than the old setup. This is how I noticed I was having a problem.
 

fullboogie

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isn't the catch can on the PVC line? I would think a blocked PVC would make for less oil in the catch can.

True, but if it's malfunctioning it might cause the problem. It's open under vacuum, closed during boost. If it's stuck open wouldn't that push oil into the catch can? At least that's how it would work with an old-style mechanical PCV valve.
 

mysticsvt

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True, but if it's malfunctioning it might cause the problem. It's open under vacuum, closed during boost. If it's stuck open wouldn't that push oil into the catch can? At least that's how it would work with an old-style mechanical PCV valve.
Bad PCV would be my first thought also.
 

70SCJ

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Installed a new PCV valve. Little to no change.
With the engine at idle I pulled the hose off the PCV valve and there was air rushing out. With the engine in vacuum shouldn't it be the other way around?
 

fullboogie

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Which end had air rushing out? The end connected to the PCV valve, or the other end?
 

nxhappy

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piston rings are shot under boost, or valves are bad. compression test needed 100%. Stop driving the car for sure.
 

70SCJ

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piston rings are shot under boost, or valves are bad. compression test needed 100%. Stop driving the car for sure.
Compression test was good. See post above. Leak down (if I did it correctly) was good as well. I have not gotten into boost and the oil accumulates.
 

fullboogie

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You should have a very strong source of vacuum at that end, not air rushing out.

So do we have an old school mechanical PCV valve, or is it electronically controlled somehow? Just not familiar with it.
 

69b302

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PCV valve is mechanical, but does have a heater on it for colder weather. The PCV flow is: metered air from the intake tube, thru the crankcase and then out passenger side into post TB blower. The PCV valve is operated by engine vacuum, so a vacuum leak could have it always open.
 

70SCJ

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PCV valve is mechanical, but does have a heater on it for colder weather. The PCV flow is: metered air from the intake tube, thru the crankcase and then out passenger side into post TB blower. The PCV valve is operated by engine vacuum, so a vacuum leak could have it always open.
Thanks, I'll work on that next.
Would the bypass valve on the SC have anything to do with it?
 

railroad

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Just put 2 catch cans on, one on my 2013 F150 ecoboost, second on my son's 2014 F150 ecoboost. Both have about the same mileage 40K. My catch can was over half full after about 1 month. Other was barely damp with oil.
I did have an oil mix up on my last change. They put regular motor oil in. Got home and noticed the ticket did not show syn. Went back and had it dumped and put in syn. Wondering if they put in 5w-20, instead of 5w-30.
 

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