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[email protected] clare@snyder.on.ca is offline
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Default Exhaust bolt choices

On Sat, 11 Jun 2011 20:15:13 -0700 (PDT), wrote:

On Jun 11, 8:00Â*pm, RS at work wrote:
OK right now I am in the process of swapping out a transmission. Â*When
was at the wrecking yard, I didn't have the right tools to be able to
disconnect the exhaust and this complicated removing the
transmission. Â*So now that I am back working on my truck I was able to
remove the bolts from the exhaust manifolds but one of the two bolts
on the flange sheared on me.

I t appears that it is some sort of carriage bolt that is tack welded
to the flange, so a couple of touches with the cut off wheel should
make it easy enough to press out.

My question is what is the best choice to replace the bolts with?
Stainless? Â*Grade 8? Â*Doesn't really matter because anything is going
to turn to snot under those conditions?

I have the anti-sieze but I am sure that the combined wisdom of this
group has an answer to this. Â*I really would like to make it easier
for the next guy, especially if that next guy is me.


Doesn't matter on the studs, I've always used what they have in the
Dorman drawers. What DOES make a difference is getting copper lock
nuts, if you ever expect to take the thing apart again. I like the
sort that has three round punch marks on the centers of the nut faces,
not the ones deformed into an egg-shaped hole. I've always used
antisieze as well, but I left it off one time on the VW and was still
able to remove the headers with no problems. Have never run across
the assembly you've described, has always been threaded studs into the
manifold on anything I've had. They make a C-clamp gizmo for repairing
busted studs, just clamps the exhaust flange to the manifold and is
supposed to be permanent, or at least permanent enough to get the
thing to a used car lot. Looked healthy enough to put some miles on,
though.

With the change in fuel, stuff isn't rotting out as fast as it used
to, less sulfur, no bromine from leaded gas, less acid settling into
the joints. So getting stuff apart isn't as big a deal as it used to
be. I've put 150K on the beast without changing out the exhaust Y at
the engine. Three mufflers later, it's still solid.

Stan

If you are talking exhast flanges, not the manifold, you can use
stainless bolts, but NOT with stainless nuts. They jam up and nothing
short of a torch will get them off. Use brass exhaust nuts on
stainless bolts or studs - or just use normal bolts and nuts and count
on likely having to cut or break them off next time.

On exhaust studs, use brass exhaust nuts whenever possible - makes the
dissassembly job a lot easier next time.

As for the lasting longer - all those points are valid PLUS the
factory USUALLY uses stainless steel ahead of the converters because
they have to warrantee them for 100,000. Many cars are now stanless
manifold to tip.