First, a little more explanation. This engine was pretty messy when I first got the jeep and I spent awhile tracking down and fixing numerous leaks. It had a Clifford valve cover which leaked a lot of oil - turned out that there is a special Clifford VC gasket, but PO had used a standard one so no surprise it was blowing oil. The grommets were loose, too. All that really didn't go away until after the head swap earlier this year, and there hadn't been any significant leakage again until now. I finally decided to get to the bottom of this "last" (
) leak, so I slathered on the degreaser and cleaned the engine really well with a pressure washer. So, at last, a clean, dry engine. The only oil I see after a bit of driving is up the distributor shaft and around where the shaft goes into the block. There is a very tiny damp spot around the dipstick tube, but I'll look at that later.
I know that leaks around both the distributor shaft (significant amount) and dipstick tube (very small) might seem to indicate blow-by, but there is no smoke in the exhaust and the engine, which had supposedly been rebuilt not too long before I acquired the jeep in early 2006, does not consume oil, so I don't think it's the rings.
There is no smoke or oil coming from any of the plumbing going through the grommets on top of the valve cover, either the breather or the vacuum line. There's no PCV valve, because this engine not only has MPFI but has been upgraded to the 4.0 head. As per the 4.0 set-up, there is a breather at the front (looks like a tiny K&N filter) and at the rear a connection from the VC to the intake manifold, the tubing and connectors for which were taken from a '91 YJ.
All signs appear to point to the distributor gasket. The distributor was pulled and modified when we added the MPFI; perhaps the gasket was damaged or lost at that time and I just never noticed the leak until other issues were fixed along with the head swap.
Not too long ago the rubber tubing connecting the vacuum line from the VC to the IM broke, and the engine did blow some oil (the VC bolts turned out to be loose - my fault from the head swap) until I reconnected the line to the intake. I'll check to make sure all the various connections are tight and tubes unblocked before I take the next step and pull the distributor.
Gasket by Felpro is available for $1.99 from Advance, AutoZone, etc. so not sure why WindKnot had to plunk down $14.99. The Felpro part is a flat gasket; I've seen people in other threads talking about an o-ring instead - is that an option? A recommended option?
Thanks for all the advice, BTW.
Here are a few photos: