Catch can full?

70SCJ

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After a few fairly short drives my passenger catch can is almost full. I'm thinking I have a big problem. No visible smoke or smoky smell.
Built/camm'd motor with pretty well most bolt-ons including a low vac bypass valve. Running about 14lbs boost on E-85 and about 6K miles. Motor has not been beat on, but had a problem a few weeks back with some misfiring which was found to be loose connections with my Vampire anti-knock system and my coils. Plugs were wet when I pulled them.
I had the SC off a few months ago to get the injectors cleaned and I'm wondering if I hooked something up wrong or did the misfires with the extra fuel wash down the cylinders?
Help appreciated.
70
 

Race Red Boss

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Roger that on the big problem. No way your catch can should be getting that much oil so fast. Hope it isn't something serious. Good luck.
 

RBB

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As others have stated, if your catch can is full after a few short drives you've got a big problem. That said, I've noticed I have more blow by and my separator fills faster on my built/cammed motor. Nothing like what you're seeing, though, I can still go quite some time before emptying it. Let us know how the compression/leakdown test turns out.
 

70SCJ

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What is in the catch can??.....E-85, Oil, or both?
Smells like oil only. Might have a hint of E-85.

Did a compression test last night and every cylinder came back with 5% of one another. I'll do a leak down test as soon as I pick up a tester.
 

biminiLX

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Good news on the compression check.
You mentioned plugs were wet, did you replace them?
What do they look like now?
Do you have a bore scope?
Who built the engine?
I’d recommend a used oil analysis.
Good luck.
-J
 

70SCJ

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Good news on the compression check.
You mentioned plugs were wet, did you replace them?
What do they look like now?
Do you have a bore scope?
Who built the engine?
I’d recommend a used oil analysis.
Good luck.
-J
I have not replaced the plugs. During the compression test they looked pretty good. Kinda grayish, but dry.
If I locate a problem during the leakdown I'll take it in for scope and I'll draw an oil sample and send it off.

The shop I use in St. Louis has an outside engine builder they use. Pretty reputable I believe.
 

Catmonkey

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How many miles had you accumulated since the last time you drained the catch can?
 

70SCJ

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More info, but not many answers. I did a leak down test and came up with the following results.
Cyl 1 8% Cyl 5 15%
2 10% 6 8%
3 13% 7 8%
4 7% 8 7%

Compresson:
1- 185psi 5- 187psi
2- 185psi 6- 182psi
3- 180psi 7- 185psi
4- 190psi 8- 182psi

I could hear a very faint air leakage in the exhaust with a stethescope and more pronounced when I stuck the stethoscope down the hole next to the leak down tube.
Am I screwed?
 

70SCJ

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How aggressive are the cams? How is the vacuum?

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.
 

RedVenom48

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Is there a way to check it or just replace and move on?
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.

Since our PCVs are electrically heated to regulate its temp, the heater element may have failed. Check to make sure you have voltage and ground on the harness side.

Not to say perhaps you dont have another issue going on, but the PCV valve is an often overlooked maintenance part. Considering how cheap it is, Id try a new one and recheck for oil in your separator.
 

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