Crankcase vent questions
 

I pulled my intake again this weekend, and I noticed that there was more gooey oil crap all in the intake and the intake valves, and it all seems to be drawn in from the front “valve” that attaches to the side of the valve cover at the front. Now i’m pretty sure that valve is what draws out the vapors from the crankcase, such as blow by, but the amount it’s drawing through that vacuum line to the intake is astronomical. I just cleaned most of the gunk out the last time I had the intake off, and now it’s back. And you can see where the hose is lined with oil as well.

Now, what exactly is that valve called? I’m pretty sure it’s sticking open, because I don’t have that much blow-by, judging that my oil consumption is about 1qt every 7.5k miles, and since I change my oil every 3k, it’s not that much oil being burnt.

Im not talking about the elbow at the end of the valve cover, i’m talking about the fitting at the very front of the valve cover, on the side. It has a vacuum line about 5/8ths inside diameter that attaches to the intake, and draws a pretty strong vacuum

The brass fitting on the side of the valve cover should be about 18 gauge or so. It is a FIXED orifice not just a brass fitting. By the way it is called the CCV system.
If the fitting has been replaced it would be larger, and let more crankcase vapors through there at a higher rate.

By the way this is on the 2.5L

The front one on the crank case isn't even a valve. It's a straight through elbow, and it gets brittle quick. I replaced mine once and was worried about the plastic bits that fell into the cover and caught on the baffle. Didn't touch it again until I replaced the valve cover gasket. Didn't touch the rear one, that appears to actually be a valve.

Good idea to replace both annually or when you change oil, before they get too brittle and the grommet gets too petrified.

The rear one seems to be doing the "metering" if any is done, other than regular vacuum action. Actually, you might want to check and make sure the right one is in there. I found a recent parts book error at O'Reilly and everyplace else that calls for the same elbow front and back. If yours is wide open on both ends, it might be evacuating too much.

Note: I am not an expert. I just notice odd stuff.

Thats odd. My fitting on the front is a metal nipple. I didn’t know it had to to be plastic…

Mine is a 1996 4.0l i6 but I would love to figure out a brass fitting solution

It's plastic on the 4.0.You have a 2.5 which I forget at times and answer with a 4.0 perspective that may not apply to the 2.5.

Looks like the 2.5 system is connected in reverse to the 4.0.

On the 4.0, the rear one has a metered orifice and is connected to the intake manifold. Using vacuum, it draws crankcase fumes into the intake to get burned off. Fresh air from the air cleaner gets drawn in through the front.

One your 2.5 (as Dusty posted), the metered orifice is in the front poking out the side of the VC. The rear elbow is connected to the air cleaner.

Make sure the orifice is clear.

LOL The OP says it is a 2.5L NOT a 4.0L.
The 2.5L is NOT like the 4.0! The 2.5L has a DIFFERENT PCV SYSTEM.

https://cimg0.ibsrv.net/gimg/www.che...ce7846e91.jpeg

Yes, my 2.5 lives in the shadow of the great 4.0.

Anyway, what’s the part number for it? Or is it unavailable?

Woopsie.

I tired to clean it. I cleaned the entire valve cover with carb cleaner, let it soak in parts cleaner, cleaned out the brass fitting and the fresh air intake side, and no change. Still getting lots of oil in a brand new intake.

But no worries. I bought a catch can from a co-worker and installed it, and what do you know, it actually catches oil. I’ve done about 200 miles on it and i’ve collected a small amount already, enough to fill up half a shot glass.

I know that lots of people say you don’t need one, but for me it’s working like a charm. I’m gonna do about 1k miles before I pull the intake again and check it out, see if it’s still gumming up my valves and getting oil in my runners.

Does your 2.46 engine's valve cover have the internal flutes like the 4.0?

Im guessing you’re talking about the ribbed metal on the top of the valve cover right? If so then yes, it does.

No. INSIDE. Like the 4.0.

CRUISER'S MOSTLY RENIX TIPS
CRUISER’S VALVE COVER MOD
NOVEMBER 17, 2015 SALAD 55 COMMENTS EDIT
Most early and even later Renix 4.0s could be bothered by excessive oil in the air cleaner box.

A fix from my old days as Service Manager at a Jeep dealership follows. Information was provided to me from a buddy at JeepTech during those days. I don’t believe it ever came out in a Technical Service Bulletin.

Remove the valve cover and turn it over. Next, remove the fluted tubes that are now facing you by removing three screws on each.

Valve cover flute

Chop 1 inch off each of them. Then, drill a half inch hole as shown in the photo. The flat side of the flute that’s closest to the edge of the valve cover. valve cover flutes (2)



Clean and de-burr/sand all rough edges nicely, clean with solvent, and reinstall. Don’t be concerned about the chintzy gaskets that will probably crumble into oblivion when you remove the fluted tubes. They can go back together without gaskets.

Here’s a handy video from my friend Brendan showing more detail.

If you wanna see the pics and video, click the link.
http://cruiser54.com/?p=131

Having learned pre internet I'm not a huge fan of how-to internet videos (a lot of them are wrong, stupid,or obscene) but that was a really well done video.

He does need to buy himself a vise.