I am about to replace the intake manifold gasket for my 87 IROC 5L. Its leaking badly (mice used to live under the plenum, perhaps their urine ruined the gasket??).This is the second time in 5 years I have had to do this. Is this a known design flaw?? The last time I torqued it to factory specs and used FELPRO gaskets as I thought this was the best that I could do. I remember breaking several bits trying to tighten the bolts holding it down, wonder if they came loose after a few months and needed re-torqueing?? Anways, wondering if there are any tricks to keeping it sealed?? (my 88 Corvette appears to be doing the same thing although not as bad). Thanks.

 

about the only thing you can do is make sure everything is clean, use thread locker on the bolts, and torque to spec.

------------------
-=ICON MOTORSPORTS=-
1st & 3rd

 

Another way is to torque all the bolts up to spec using the recommended sequence, then let the manifold sit for an hour or so and then re-torque them to spec.

Usually the gasket will compress slightly during that time causing the torque to lessen and the re-torque makes sure they bolts remain at the spec torque.

Depending on the kind of gaskets you're using and their thickness you may have to re-torque them more than once. On occasion, I've done this two or more times just to be sure.

I've got a complete "How To Do It' file I can send you if you'd like. I've been following the procedures in the file for many years and in insures the manifold will remain leak free. It's also the same procedure - with just one slight modification - that I see printed in some of the 'Tech' articles in the magazines.

Hope this helps.

Jake

------------------
1986 Corvette Coupe, 415 CID, Edelbrock 6073s, ZZ9

[This message has been edited by JakeJr (edited November 21, 2000).]