Exhaust manifold stud broken

[Yuta]

Hi all,

I got a 1993 mighty max with 8-valve 4G64 engine. Vehicle has 190k miles. Currently I discovered the exhaust manifold studs are broken, the first one and the last one. Good thing is the remaining stud is still above the surface. Questions are:

1. How to do stud extraction? What kind of special are helpful?
2. Can I do stud extraction without taking of the head? Looks like there is plenty space if I take off exhaust manifold. Anybody ran into similar situation?
3. Where can i get high quality exhaust studs? I don't want this happen to me agian.
4. If I don't want to fix it now, what is the risk? The whole exhaust manifold fall off? I only use this truck as a spare vehicle. Very trip is short distance, usually less than 1 hour. I am thinking of rebuilding engine in 1-2 years. So if I can keep it the way it is now, that would be great.

[geezer101]

If there is still some of the shank exposed after taking the whole manifold off you might be able to get enough of a hold on it with a pair of locking jaw pliers and undo them. If you don't replace them the worst thing that will happen is an exhaust leak from the manifold. It will run like a pig but it'll run. An as for replacing them just go to a junk yard and pilfer a few off any engine with the same pitch thread (they're metric so pick something out of the same family - DSM, Hyundai, Kia, Mitsubishi etc)

[noahwins]

That last stud breaks pretty often. I've had pretty good luck with these, but screw and bolt extractors generally all suck.

14901

There's also the welded nut method:

https://www.facebook.com/SpeedSociety/videos/1256232607727372/

There are a few bags of OEM studs on eBay right now:

http://www.ebay.com/itm/New-Nos-Oem-Mopar-Mitsubishi-Exhaust-Manifold-Stud-MD041256-Lot-of-8-/171649771517?hash=item27f71fa7fd:g:Vx4AAOSwWKtUvmZ 7&vxp=mtr

http://www.ebay.com/itm/Mitsubishi-MD041256-Exhaust-Studs-pack-of-8-/321211870055?hash=item4ac9b82b67:g:xasAAOxy5rpSO0L e&vxp=mtr

[pennyman1]

you can also use a socket made for rounded nuts if you can find one small enough to bite the shaft.

[LSR Mike]

Replacement studs can usually be found at a good hardware store, no need to go junkyard hunting for them. you can do it on the truck. I replaced all of mine on the last re-build, not a hard job...

[unc25]

What is the correct size for the exhaust manifold studs?

8x1.25x ??????....I need to know the correct length in order to get replacements and I can't seem to find anything definitive.

Sorry to bump an old thread but I've asked in the Facebook page with no response.....

[LSR Mike]

Well I spun out one of the good one's and went to the Hardware Store and did a Stare & Compare. I also picked up fresh nuts.

[unc25]

That was my plan, but it seems that I can only get the broken one out ( go figure) ....so I'm gonna have to guess a bit.

I do know it's not 55/56 mm as I've already ruled those out....going to give it another go today and see if I can find the right one.