Are 4.0 valve covers head specific ??????? -
LinkBack Thread Tools
post #1 of 2 Old 07-20-2009, 03:03 PM Thread Starter
Registered User
1985 CJ7 
Join Date: Dec 2008
Location: Ohio
Posts: 48
Are 4.0 valve covers head specific ???????

I just completed a 4.0 head swap on my 258, I got a valve cover off a buddy since my new head did not come with one. This valve cover does not seal to the head. Bought the $36 fel-pro perma dry gasket and leaks like a cive.... I was told that the valve covers are head specific such as to each casting #. Any help would be great my casting # is 0630 and the valve cover im using has a lip around the bottom which is not letting it seal to the gasket.

Bruner3 is offline  
Sponsored Links
post #2 of 2 Old 07-21-2009, 09:14 AM
Registered User
Join Date: Jan 2008
Location: Virginia
Posts: 4
the answer is ... sort of... the early 4.0's will interchange with a 4.2, I believe the 91 to 95 might as well though Ive never tried to interchange between a renix (86-90) or 91-95 with a 4.2 valve cover or vice versa.

The 96 and up is a stamped steel valve cover, as you've found the head is slightly altered so older covers don't fit without grinding that lip off. So that's why it's "sort of" you can easilly grind that lip off and achieve a decent seal using the 96 and later rubber pre-formed gasket. It uses rubber o-ring style reuseable gasket And it's the best valve cover/gasket combo ever made for a AMC straight six IMHO anyway...

The steel helps, but the thick rubber gasket with crush spacers in the cover to keep one from torquing the cover down way too much and distorting the cover is the least leaky of them all (by far) in my experience.

Simon check out
1bolt is offline  

Quick Reply

Register Now

In order to be able to post messages on the forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Jeep Forums Replies Last Post
valve covers CherokeeTank Engines & Drivetrain 1 05-17-2006 09:23 PM
4.0 valve covers creepinjeep90 Engines & Drivetrain 1 04-13-2005 06:05 AM
leaky valve covers! Marc CJ7 Engines & Drivetrain 5 07-06-2004 07:46 AM
Aluminum Valve Covers mud4me Engines & Drivetrain 7 05-29-2002 08:15 PM
Valve Covers bigjeep39 Engines & Drivetrain 5 12-10-2001 05:19 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome