2.5 Valve cover gasket question

[pitbull4x4]

I have the plastic valve cover on my 89 Comanche with a 2.5 in it. I got a good deal on a aluminum valve cover off a 2.5 out off a 94 Wranger. Which valve cover gasket will I use? The 94 or 89? I was told they are differnt. The 94 valve cover had a rubber one on it.

[dasbulliwagen]

I'm not sure if the alum cover needs a special gasket or not, but with the plastic ones, there were two choices depending on which bolts you had to hold the cover on with. It may be the same for the alum cover. There is a bolt that has a shoulder that goes through the gasket to prevent overtightening, and then there is a shoulderless bolt. I assume the shoulderless bolt has the tightening limiters built into the gasket. Thats the route I would take if I were you. Just see what bolts you have and order appropriately. Good luck.

[txjeeptx]

The aluminum valvecover has tightening limiters cast into it around the inside of each bolt hole. You will have to use the '94 valvecover bolts, since the ones for the plastic cover won't fit in the aluminum cover's holes. I don't use a gasket for the 4banger valvecovers - just a very healthy bead of RTV silicone. The AL valvecover came with a bead of silicone rubber already on it from the factory(I have bought one from the stealership before), so there is no separate gasket for it, although there are gaskets available from Fel-Pro for the AL cover, so you could source one and still use some RTV on both sides of the gasket. Its much easier to just use a fat bead of RTV and make sure to not leave any gaps where oil could leak. I put some RTV on the head after cleaning the head's gasket surface, then the fat bead of RTV on the valvecover, then bolt it on to where some RTV squishes out from every edge(just past hand-tight with a socket wrench, tighten in a sequence starting at the middle and working a spiral outward, some cleanup required before RTV sets up), then let it set up, then do a final torque of the valvecover bolts the next day.

 

For the PCV, I removed the baffle from inside the AL valvecover and drilled a hole for the PCV grommet with a properly sized hole saw, then reinstalled the baffle(3 small screws inside the cover - use locktite blue on them). I put a small pipe plug in the CCV port that goes into the baffle where you install the PCV valve into. Get a new PCV grommet and fresh 710 cap to prevent oil from weeping out of an old cap gasket. I recall having to swap out the rear fresh air inlet grommet with one that fits the stock TBI fresh air inlet breather filter plastic can.

 

All this was on my 2.5L YJ, which might have different breather setup than what was on the XJ/MJ valvecovers, which might be CCV not PCV, so you might not have to do the baffle-pull-holesaw-drill for a PCV grommet.

[pitbull4x4]

Thanks for the info. I got it changed today. So I will be looking very hard to see if any oil leaks. So far none. :banana: