Broken Exhaust bolt/stud


Registered User
Truck is a 1995 Gmc 3500 with a 350. The back bolt on number 7 cylinder is the broken in the head. I replaced the exhaust manifold 4 or 5 years ago because it was cracked. The bolt was broken back. i didn't fix it just put new gasket and manifold on it. well that gasket is blown out and I have to fix it to get the truck though inspection. Is there an easier way to get it out other than pulling the wheel well and drilling it out? Easy outs and me don't seam to get a long.


it's a man, baby!!!
maybe pull the manifold and have it surfaced to make sure it gets the very best coverage possible, use the copper gaskets, pass your inspection then sell it


as a matter of fact i dont have 5$
Copper gasket and a layer of jb weld.
JB weld can't take the heat of an exhaust port. Best thing to do is to pull the inner fender pull the exhaust manifold grind it flat to the head, center punch it and drill it out with a left hand drill bit. I would soak it with PB blaster for a day or too first, you can then decide if your going to be able to save it and tap it or have to put a heli coil in the hole. Depends on how good you are with a drill.

So. Good luck bro.


I like fistables.
A helicoil is just wrong in an exhaust manifold. Someone is going to curse you later. I guess if you don't mind being cursed but I'm not taking that chance.
They don't make a self-tapping bolt? My old Dodge Durango was famous for stopping clipper bolts, they made a self-tapping replacement for it.


as a matter of fact i dont have 5$
You still need to get the broken stud out before you can use a self tapper.


Registered User
The way i have removed them in the past is weld a washer on to the part of the stud that stick out and weld a nut on to the washer and remove it.some one told me that Stainless does not stick to cast iron and to use stainless wire to build up the stud and then went the washer and nut on that. i never welded on to cast iron before so dont know if the stainless will only stick to the stud and not the head


as a matter of fact i dont have 5$
its the heat that loosens up the stud, not the weld, cast does not like being welded on no matter what you use. every time i have ever tried to weld anything onto a broken stud i just end up breaking it off lower into the part, if the stud is just shitty and broke because someone over tightened it in the past (torque to yield) you should be able to soak it with PB blaster and turn it out with a left handed drill bit, if its rusted into the head (most likely) your fucked.
i rounded off a brake bleeder the other day and never got it to loosen up, im dreading drilling it out to the point that i might just order a new caliper and get it over with. i have retard patience when i was working on my harley i broke two bolts off in the timing side of the engine case, i spent about 20 hours drilling out and re tapping the case, using dental drill bits as it was i ended up fucking up the threads in one of the holes and ended up using that as seen on TV aluminum shit ot repair the the hole with it worked well since i was afraid to tig weld on the block.


I don't know shit about welding

But the shop up the road couldn't get the bleeder screws outta the front calipers on my truck
And they are damn good mechanics
I had soaked them in PB beforehand , but decided to let them deal with it
Fuckin' rusty as shit underneath


I like fistables.
Welding on a head may not be such a great idea what with the head gasket and all. If you're gonna go that route may as well just blow the rest of the bolt out with a torch. And yes the bolt only can be blown out with a gas axe with out harming the threads, the gasket most likely would not last long after the focused heat tho.


Screw you guys, I'm going home.
Whatever you do, use the anti seize compound with the new bolts.

Good luck bro.