Valve cover questions

[Steve Gregory]

I'm going to put on a new style valve cover on my 89, and I have a couple questions. Is it a direct bolt in? Are the gaskets interchangeable? That's about it. Thank you!

[HOrnbrod]

http://comancheclub.com/topic/12217-ho-valve-cover-on-a-renix-40-update/?hl=valve+cover

[Steve Gregory]

Thank you, that's a very informative thread!

[75sv1]

^{I have put a '95 VC on my '89 Comanche. I think there are three styles. The one I used had the 90 degree turn fittings (91-95). The two others had the latter style grommet PVC fittings. I have two at home. One was on a '94. I have only seen a picture of the last style, or its my imagination. Same grommet PVC, but a slant to the VC.}

[Rockfrog]

There was...

the 87-90 Renix, smaller holes and molded system, aluminum VC.

The 91-~94ish HO, 1/4 turn CCV nipples, aluminum VC.

The 95ish (maybe only 96) HO, pop in grommet style nipple, aluminum VC.

And then late 96 up stamped steel VC with pop in grommets and CCV hose nipple.

 

I have the late model stamped cover on a 92 head on my 88 block MJ. I also have a 91 VC on a 93 head on my 00 block XJ, but at one time had a Renix VC as well. Use the gasket that matches the year of the cylinder head being used. So 87-90 (2686), 91-99 (7120, 0630), and 00 (0331) up.

I personally prefer the stamped steel cover as they seal better than the aluminum covers, and corrosion is less of a concern, the aluminum cover on my XJ looks pretty crappy after 3yrs in new paint yet it's original stamped cover still looks new on the MJ. Good thing I snagged another 00 VC to fix that.

 

 

Sent from my SGH-I337M using Tapatalk

[schardein]

I've converted all three of my 1991 4.0 motors to the later model stamped steel cover using the blue molded/steel core gasket.  I got all three from the junkyard, including the gaskets and all three sealed up and still good years later. 

 

Plastic nipples and rubber grommet replacements are available for fairly cheap off amazon.  I've got the part numbers in the garage if you need them.  If a nipple is broken, you will likely have to destroy the hardened rubber grommet to replace the nipple.  Plan on replacing both. 

 

Also I seem to recall that the swap requires a different (or modded stock?) breather hose to the factory airbox. 

 

Recommend getting everything (VC, gasket, bolts, hoses) if getting it from the junkyard.  The places I go don't charge anymore for the other stuff and it comes in handy. 

[75sv1]

Basically, the rear one goes to the intake manifold. The front one goes to the air intake box, or some just put a small breather element on it. Not sure of all the tubing etc for the Renix for that. Taking it off or to the air box, would help with 'Blow By' or oil being sucked into the air filter.