I recently replaced the CCV plumbing on my XJ since I was having problems with oil blowby into the air cleaner. Anyway, the rear valve cover grommet doesn't mate up with the elbow. The grommet I've got is round while the elbow fitting for the rear vacumn line isn't! Is it possible to buy just a new grommet or do I have to buy an entire new valve cover?
You have a new elbow, and it's not round? There should be no reason to replace any of this system unless it's broken, there are no wear parts. When you notice oil in the airbox, you have a plugged=20 orfice. Clean the orfice and your job is done.
Let's get clear... is the elbow new? Is the grommet new? Was the old elbow plugged up? Did you=20 already throw it away? Was the old elbow round?
I think we can safely say that you don't have to buy a new valve cover. __ Steve .
I don't have a clogged orifice in the rear valve-cover CCV plumbing because it's not really connected at all. That's the problem the grommet in the valve-cover doesn't match up with the CCV elbow fitting. The grommet in the valve cover is merely a round hole whereas the CCV elbow fitting is designed to be rotated and locked in place (kinda of like the oil filler cap) rather than just plugged in.
The CCV plumbing is all new because I was having oil blowby into the air filter. The problem is the rear valve cover CCV plumbing never fitted so there's plenty of room for a vacumn leak and I'm pretty sure nothing is being ported from the valve cover to the intake manifold because the connection is so loose.
Because of all the above I'm thinking Jeep/Chrysler/Damniler must have changed either the rear valve cover grommet design or the valve cover design since '91'.
I think I'll look into Bill's idea and see if I can find and elbow that will mate to the existing grommet and CCV plumbing.
91 and I believe 92 used the twist in elbows with a rubber gasket on the elbow. You either have an earlier or later design valve cover. If you have the later design (bigger holes), you can use the later elbows and grommets. If the valve cover is an earlier design (smaller holes), you'll have to rig something.
OK... all my XJs (93, 98, 00) had round holes...=20 =20
I see... the round hole is an improvement! The tangs made it leak more... any slight leakage and your crankcase is not evacuated. =20
Yes, I can certify that.
Exactly...=20 __ Steve .
The parts guy at Jeep tracked down the right CCV assembly: 10 bones for 2$ worth of plastic. Apparently the Cherokees have featured at least two different valve covers.
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