I am getting ready to replace the VC gasket on my 91 XJ, and I had a quick question.

The two orifaces, the front and back ones with the elbows with hoses going to the air box and intake manifold, I think need cleaned. I have oil in my air filter, and I looked at a how to and I think inside the VC there are two components you remove and just clean/scrub the hell out of. But what about the 2 elbows? They seem as though they can screw off.. Do these replace too?

Thanks everyone.

 

I'd replace them myself. They are not expensive valves.

 

Where do I get them? I looked on AutoZone, and the only ones they have say for use without an oriface..

 

Ahh, wait a min. I just went back and looked.. and stupid me I think it means it is sold WITHOUT the oriface.. Stupid me.

"Back of valve cover, without orifice"

 

the one on the back is the pcv valve, you should take it off with your jeep running and see if vacuum is getting through it, you can also pull off the hose that connects to it and make sure it has vacuum, the valve is only 10$.

 

Check this out.


https://www.cherokeeforum.com/f2/whe...located-11228/

 

That is quite an entertaining thread. My Haynes manual states that the later models have the CCV system which is basically a hose that goes into a rubber grommet on the valve cover. Seeing how yours is a 1990 it should have a pcv valve which is set on the rear of the valve cover, with a hose connected to it (which should have vacuum in it), the valve will twist right out, very simple, I just cleaned mine a couple weeks ago, you can buy a new one for about 10$ at Autozone. Another part of testing the valve, aside from checking for vacumm is to take it off and shake it, it should rattle inside, if not it is bad.

 

the 4.0 does not have a PCV valve, they use a "CCV" system. Just two holes in the VC with a metered orifice underneath.

Here is how I did my VC
http://i25.photobucket.com/albums/c8...s/d28ad740.jpg

 

Then why does my Haynes manual say there is one? Why is it that I can pull one up for my 93 4.0 on Auto Zones web site? Why does it look just like the picture he posted? Why does it twist right out of the VC with no rubber grommet, like the Haynes manual states? Why is it NOT a hose that goes into a rubber grommet on the VC like the Haynes manual states for a CCV? Defiance, I looked at your engine bay pics and the hose that goes into the back end of the VC does look different than mine. So maybe you don't have one, but like I said mine is different.

I was thinking what they call a PCV Valve might just be an empty elbow piece, I would have to get my hands on a new one to see if it rattles to really know. But either way they still call it a PCV valve.

 

No PCV on the xj it is called CCV you can get all the parts at the dealer for under 15 bucks for front and back The HAYNES BOOK has a ton of mistake PCV is just one of them you must have seen some of the mistake by now if you know anything about an XJ. NO RATTLE EITHER.

 

Look... I don't know **** about XJ's..but I know the Haynes manual says that a CCV, is a hose that goes into a rubber grommet on the valve cover and the PCV is a plastic elbow piece that twists right out(which is what I have)... I know I can look it up on Auto Zones web site... I know I can READ ENGLISH!!! Just Kidding bro...hahahaha........Whatever.....it's probably just an empty piece of plastic elbow that lets vacuum through and not an authentic pcv valve, but it still calls out a PCV valve....just clean the damn thing and make sure vacuum is getting through it on the rear side....

 

I'm replacing the VC gasket on my 95' in a week or so myself. Like the topic post, I have oil leaking into my air filter. Is that an indication that the elbow is leaking oil out from itself? The line leading to the air filter is coated with dirty oil.

 

Your gonna get a little blow buy. Its is nothing new. I can pull my filteron my gsxr and have a little also on the filter. But if you have a massive amount of oil then you have other problems.

 

twist off the elbow on the back with your jeep running, see if it has vacuum in it, if not it might be clogged (you can clean it out with a paperclip, needle, lashing wire, etc...), pull the rubber hose off the elbow and check that for vacuum, if something is clogged than that can cause some of the "blow by".