Exhaust Manifolds

[steven d. ferguson]

Nate,
I read as many of the posts on this issue as I could find. I bought
the Napa ones, I forget who really makes them, put them on with new
grade 8 bolts and ran the coach for an hour or so. The next day I
retorqued the manifold bolts, and drove the coach for a couple of
hundred miles. Sometime later, before I started it again, I rechecked
the bolts....about as tight as as when I last retorqued them. This is
the way I've dealt with headers and cast iron exhaust manifolds since I
can remember. They still do not leak. I did not resurface the flange
surface, the original gasket pieces I removed seemed to be the source of
all the leaks so I thought I'd try just replacing the gaskets first. I
did all the work through the inside hatch, it probably would be easier
to do it from the outside with the fender wells removed but that's just
the way I did it. Took about 2 hours and 3 different wrenches. Not a
bad job, just awkward.
HTH,
Steve Ferguson
San Diego

 

[steven d. ferguson]

Nate,
I didn't use any goop. I believe it is a good policy to do so but I have
pretty good success without it. I've watched Ed Hanson do a lot of header
installs and he always uses the stuff.
Plenty of room to scrape the gasket remains off. I did not use never seize on
the bolts. The manifolds I pulled were the originals with what was left of the
original gaskets, (not much), and they cleaned up pretty easily. The original
bolts were easy to remove also. If you decide to replace your existing bolts
with new G-8's, make sure you select the correct length. I installed them first
to see if they were bottoming out, then slipped the manifold in & bolted it
down.
I guess some folks have had some real problems with warpage, erosion etc. I
haven't on my GMC nor any other vehicle I've had, which is a bunch of 'em. I've
never used a torque wrench on manifold bolts either. I just reef 'em down, run
it, let it cool, do it again, run it & then repeat the process. I must be
lucky.
Just love that single muffler 3" system. It's like driving a new coach!
HTH,
Steve Ferguson

> Steve,
> Hey, thanks for replying... say did you use any goop on the gasket and if
> so what kind and on what side (or both)? Did you have to loosen the header
> flange at the end of the headers to get enough room to scrape the gaskets???
> I have retorqued my headers 4 times now and they are always a bit loose.
> Also do you use never seize on the bolts? Thanks for letting me pick your
> brain, guy!
>
> Nate
>