Rear Engine Oil Leak

[slack]

All,

Any ideas what could be common reasons why my engine would be leaking in the back? The front of my car is bone dry. I actually have to throw another coat of rust paint on the oil pan because it's getting surface rust. The rear of the engine is wet though. That emission exhaust piping for the AIR system that crosses under the trans has oil on it to the point it basically drips off.

It looks like it's coming from high up, but I wasn't able to see anything conclusive peering in with my flashlight. Valve covers? Intake?

Also, I'm looking to replace the hoses that run under the plenum. Does anyone know what hoses I need for that and if there's a lot of stuff that needs to be disconnected?

Thanks!

[sly]

PCV valve come loose, screen clogged, grommet bad, lower intake gasket bad, valve cover gaskets bad, rear main seal, oil pan seal... I think that's all the usual suspects.

[slack]

Thanks.

So it looks like the only real big PITA ones would be the rear main seal and the oil pan seal. I'm going to rule out oil pan as the oil is leaking up higher than that. (Unless it's leaking as well as somewhere else which is possible).

I'm guessing when I take the plenum off, it should be a little easier to tell right?

PCV valve and screen are < 2 years old. Grommet might be bad... I didn't replace that.

[gadget73]

The rear main seal and the back of the pan gasket are rarely the problem. Oil coming down from above is way more common. Have a look back there with a flashlight. If the top of the trans is all juicy, its coming down from the top.

[sly]

Even when I did replace the PCV grommet, I had to use ultra black RTV between the grommet and the lower intake to keep it from leaking in the Mad Marquis.

[slack]

Awesome. Thanks guys. I'll take another look and see what I find.

[packman]

Could be the rear of the valve cover(s). I recently had to retighten the valve cover studs (replaced the bolts years ago) because they had gotten loose. If you haven't changed the valve cover gaskets recently, you might want to check them. My CV leaks mostly when standing still.

My Ranger leaks when running. Valve covers have stripped bolts (possibly the holes too). They don't leak when it's parked like my mom's CV does. I think it's the rear main seal. Go through a quart of oil a week now. I will fix the leak or discard the engine; whichever is fastest.

Packman

[gadget73]

Even when I did replace the PCV grommet, I had to use ultra black RTV between the grommet and the lower intake to keep it from leaking in the Mad Marquis.

I used large heat shrink with a fairly heavy wall to make the PCV valve fatter. That makes the grommet seal pretty good. The grommets you can get are not quite exactly the right size, so things fit loose.

[sly]

this grommet fit to the valve pretty good... but not to the intake.