problem with exhaust manifold stud
 

well today i started taking off my exhaust system and unbolting things to get ready to put my new RB header on.

i decided to start with the hardest of the four manifold nuts, the top one closest to the front. i basically just used an extension and a breaker bar. it SEEMED to work fine, until i reached down and grabbed what i thought was just the nut, but for whatever reason the whole stud decided to come along for the ride.

https://www.rx7club.com/attachment.p...d=177770&stc=1

what would be the best thing to do in this situation? the thread on the stud still looks in-tact. i'm not too sure where i would fine a new replacement one (i'm guessing hardware store that sells metric stuff), and i have never replaced a stud before.

I dont know if this is the right thing to do or not, but when that happened on my accord i just put it back in as if it were one big bolt.

Yes, put some loc tite on it and thread it back in there good. That's all there is too it. I took mine out on purpose recently because I couldn't get the engine out and my exhaust is welded from the downpipe back.

i would replace that!!
you dont want to put a weakend bolt back in their...what if you put it back in and need to take it back out and it breaks?

i think replacing the stud(s) that end up coming out is a good idea. hopefully i can find the proper size at a store (i have never seen metric studs sold anywhere locally, but i haven't really looked).

then i have to figure out how to put the stud back in. it involves using two nuts i think?

thanks for the replys.

You thread the shiny part of the stud (where it is less corroded) back into the exhaust manifold. Do you see where it stops being shiny, there is no thread there. This prevents it from going too far. Thread it up with lock tite as far as it will go. Then take the nut off, and stick the downpipe on (with a gasket), and tighten the nut up with a lock washer. There you go.

I pm'ed you about That Aaron..the stud will only go so far..then it hits the part of the stud where it has no thread..If you are using the same stud,what you will have to do is to make up the difference with washers,between the Nut and the header(due to the header flange being thinner than the Stock manifold).You could also get another exhaust stud...OR..you could try to Thread the stud(with a tap and die set) to accept a nut that would go between the Nut and the header..What you DO NOT want to do is to try to force the Stud into the housing.It will strip the Hole and you will Regret it Big time...I ran into the SAME thing when I took off my Stock Manifold.The Washer trick worked fine.In fact it is still holding.Just a little addition though..when you put the Header on,after you have it on for a couple days,go back and Retighten the nuts. The header will have settled into place and the nuts will require another turn.(at least mine did.which I'm assuming is only Normal)

well, this is the only stud i could find that was the right size and pitch (M10 x 1.5):
https://www.rx7club.com/attachment.p...d=177879&stc=1

the length though is different. would that be ok to use?

so anyone know if that stud will work fine?

Looks like almost half as much thread area as the original. You might have a problem with ti backing out. Can you run a die down it to lengthen the thread?

I don't really see what's wrong with the original stud assuming you can get that nut off.

i don't have a die for that. that is what i am weary about, having half the threaded length.
you are right, i don't think there really is anything wrong with using the old stud, other than the fact that it is an old stud. a new one would be prefered, but i think if i can get that nut off fine i will just put that old stud back in.

i just didn't let the penetrant i sprayed sit for long enough. i waited a day on the other nuts and they all came out fine.

by the way, does anyone know the tightening torque for the exhaust manifold nuts? i can't seem to find it in the FSM...

found it...tightening torque from Racing Beat is 25 lbs/ft.
well, i think i got it installed fine. just have to make a pipe from the header to the y-pipe now.