Oil leaked on me twice on the valve cover passenger side near oil fill cap. PIC>

[5ABI VT]

Hi guys yesterday I drove the car over 1000km to and from an airport half mile event and the only issue I had was twice I noticed a little oil burning smell and when I popped the hood I found oil on the valve cover near the oil fill cap. The cap clicks but is loose /jiggly making me think it's coming from there. There is a catch can on the motor and it did pull about 2 tablespoons.



Is the oil fill cap tight when you guys tighten yours down ?

[32valvesftw]

I think here is a seal on the cap, maybe it has a crack?

[Dynomite]

A. Billet Aluminum Oil Cap
Search Ebay CORVETTE C4 LT1 BILLET CHROME SCREW IN STYLE OIL CAP Ebay Billet Aluminum Oil Cap (fits 90' & 91' LT5 & L98).
The Billet Aluminum Oil Cap has an "O" ring.

[XfireZ51]

My suspicion is that it's coming from the vent tube. The likely culprit is the vent filter in the cam cover. Ask me how I know. The burning oil smell happens during WOT runs. During cruise, no problem, right?

[Dynomite]

Originally Posted by XfireZ51

My suspicion is that it's coming from the vent tube. The likely culprit is the vent filter in the cam cover. Ask me how I know. The burning oil smell happens during WOT runs. During cruise, no problem, right?

I would concur but it appears oil has dripped down from around oil fill cap.

[XfireZ51]

Originally Posted by Dynomite

I would concur but it appears oil has dripped down from around oil fill cap.

True Cluff, but it would not have gotten over by the cam cover bolt and into the spark plug valley. You can also see some seepage right by the vent tube as it enters the cam cover.
Something is causing a pressurization of the crankcase and I don't think it's the oil cap.

[5ABI VT]

Originally Posted by 32valvesftw

I think here is a seal on the cap, maybe it has a crack?

Looks like it has hardened but the o ring is there and not torn. When the cap is tight .. It jiggles sideways and up and down a little bit like its loose even after it clicked in after tightening.

Originally Posted by Dynomite

A. Billet Aluminum Oil Cap
Search Ebay CORVETTE C4 LT1 BILLET CHROME SCREW IN STYLE OIL CAP Ebay Billet Aluminum Oil Cap (fits 90' & 91' LT5 & L98).
The Billet Aluminum Oil Cap has an "O" ring.

Will look into that thanks ! I don't want a billet cap but I can probably pc it to match. In the meantime it might have to do !

Originally Posted by XfireZ51

My suspicion is that it's coming from the vent tube. The likely culprit is the vent filter in the cam cover. Ask me how I know. The burning oil smell happens during WOT runs. During cruise, no problem, right?

I thought of this but the little area around the base of the vent tube is completely clean of oil.

Originally Posted by XfireZ51

True Cluff, but it would not have gotten over by the cam cover bolt and into the spark plug valley. You can also see some seepage right by the vent tube as it enters the cam cover.
Something is causing a pressurization of the crankcase and I don't think it's the oil cap.

It's definitely around that area and it's the very first time I've seen it. In response to you again xfirez51 no it doesn't seem to be under wot. I did 3 half mile runs and some more wot back down the runway and when I popped the hood all day between runs the cam cover was clean.

I noticed the first time after steady highway cruising after about 250 miles just pulling into a rest stop. It looked the same as it did when I took the pics I posted above. The second time was when I almost reached home dropping off my friend at home. I'm wondering if it could be from hard braking ? Would enough oil reach the oil fill cap?

I'll take a video of how loose the cap is when I get home from work.. Just curious if it's normal. Thanks everyone for the input!

[A26B]

I looked at your thread discussing your plans for oil catch cans. Can you show a diagram and/or photos of what you actually did?

FWIW, I don't think it's a good idea to put catch cans on the cam cover fresh air inlet tubes. I think it will hinder the function of the PCV system by adding restriction to the fresh air plumbing.

[5ABI VT]

Originally Posted by A26B

I looked at your thread discussing your plans for oil catch cans. Can you show a diagram and/or photos of what you actually did?

FWIW, I don't think it's a good idea to put catch cans on the cam cover fresh air inlet tubes. I think it will hinder the function of the PCV system by adding restriction to the fresh air plumbing.

No catch cans on the fresh air tubes. Just from rear pcv to can and from there to the hard line on the plenum back to the intake

[5ABI VT]

I'm going to pull the o ring off and see if the cap still jiggles around the way it does. I'm assuming the o ring should help it fit a bit snug ?