Oil Backing Out of Dipstick Tube ...

[Tim_in_NC]

Hi Guys ...

The last couple of driving sessions that I've had ... there is no issue with any smoke after the first or second boost run ...
However, after that I begin to see a smoke screen behind the car if I hit boost again ... Normal driving is fine, no smoke of oil on header, etc ...

The 1st time this happened I pulled the car in and noticed oil on the drivers side header (was hard to pinpoint the leak as Oil was on rear of valve cover, head, dipstick tube, headers, plug wires, etc...) This 2nd time, I finally noticed the dipstick wasn't seated (pushed out) so I'm assuming oil is backing up and out through the dipstick tube ...

I have one breather on the passenger side valve cover and did notice a little fluid backing out there but it was minimal ... The drivers side has a PVC (Hose from Valve cover to rear of Carb) ...

Do you have any recommendations for me to prevent oil from backing out of dipstick tube under boost ...

Thank you ...
Tim

[Tim_in_NC]

I'm uploading images of my current setup ...

[Tim_in_NC]

After speaking with a local engine guy, he recommended adding a 2nd breather and keeping the PCV valve. Looks like I might need new valves covers as I'm not sure how to drill these ribbed covers for a 2nd breather ... I'll also probably get better breathers while I'm at it. Any recommendations ???

[72BBSwinger]

Attach a breather and hose to the dipstick tube. As long as that PCV is closed under boost it will work fine.

[shmoov69]

Issue is crankcase pressure. You can mask it with a PCV and breathers, but you really need either better ring seal, or a vacuum pump. Better yet, both! A good vacuum pump will help the engine tremendously. They make an electric one if you can't do a belt operated one.

oh, you can zip tie the dipstick down to help mask the problem also.

[LS1-IROC]

This is very typical on a boosted engine with not enough crankcase venting. I run a catch can/breather for both sides of my engine and have never blown a drop of oil out of the motor. Ditch the PCV system and run dual breathers with a catch can. Problem solved.

[Tim_in_NC]

Thanks for the replies guys ...

What I'm planning to do for now is install 2 of these Moroso Breather/Tank Setups and run braided hose from the top of each valve cover to the tanks ...



I'm assuming 10 or 12 AN Fittings/Hose will be fine, correct?

Also, anyone have a source for AN Fittings that have a Barb on the other end to push into the rubber grommets on top of my Valve covers? I'm having a hard time finding them ...

Thanks again,
Tim

[LS1-IROC]

The bigger the line/fittings, the better it will work. If you use too small of line, the velocity of the vapors will be to high and have a harder time condensing in the tank. I'd opt for the 12AN if you can package it. I run 8AN on mine and it works fine, but I only did that for packaging.

[Tim_in_NC]

The bigger the line/fittings, the better it will work. If you use too small of line, the velocity of the vapors will be to high and have a harder time condensing in the tank. I'd opt for the 12AN if you can package it. I run 8AN on mine and it works fine, but I only did that for packaging.

Sounds Good ... thanks!

[65 ELKY]

You are most likely getting boost pressure through your pcv. I'm putting a check valve before pcv. A $4.00 part maybe all you need.