Exhaust Manifold Bolts Removal

[prairie]

Need to install new exhaust manifold gaskets on a 350 Chevy engine. Is in a 91 pickup so everything is fairly easy to get at.
I have never done this before, and have heard that it is common to break a bolt or two in the process.
Any suggestions on minimizing our chances of breaking bolts? And, when/if we do, any broken bolt removal tips?
Was told to coat them liberally with anti-seize on re-assembly.

 

[K85 Octane]

PB Blaster every couple hours, saturday and sunday Then take them off with hand tools. Bout all you can do.

 

[454Sub]

Heat can help. And coating them in antisieze will just make them work loose.

 

[ratlover]

Heat is your friend if it appears stubborn although u gota be careful swinging a torch around obviously. Presoaking with a penetrant won't hurt either.

Here in central IL those studs rust to the point of looking like tooth picks so u just plan that they are breaking

Just have a back up plan if u do snap one. if it's your only set of wheels I'd have some new studs, exhaust manifold gaskets, torch handy before u start You can take it back if u don't use. Can also hit it with a torch with it still attached to the block but I'd prob take the extra time to remove if u break one. At least have ability to pull manifold off head and take it somewhere to get new studs put in(I guess u could drive on an open manifold too )

If you break it's easiest IMO to pull the manifold off the head, hit the man around the stud with a torch, then go after it with channel locks or vice grips. Might as well replace em all too. IMO a propane torch also don't work worth a piss

 

[454Sub]

Blah, I hate rust belt IL sometimes. But after a year, I never have to worry about parts coming lose.

 

[Big Ray]

PB Blaster every couple hours, saturday and sunday Then take them off with hand tools. Bout all you can do.

this...^^

easily removed the manifolds on an 89 in 05. with a six point wrench. gets a good grip on the bolt.

 

[diesel4me]

The bolts often get seized where they pass thru the manifold,and chances are good they will snap off flush with the head,if your lucky enough to be able to grip whats left of the hex with a 6 point socket...

If one breaks,I usually leave the manifold bolted up,and use it as a drill guide to drill out the busted peice,by using a 3/8" drill at first,to help make a centered point for a smaller drill (3/16) to drill thru the remains of the bolt,then go up in sizes until you reach 5/16" and then you can tap it out to 3/8" coarse threads...

Here,many manifolds litteraly crumble away after 10 years,and its a suck job to get them off without breaking most of the bolts off in the head...my friend who does many replacements has found the best way to get them off is to use a sawsall to slice the manifold off lengthwise,they cut easily when rusted thin,and then the outer portion can be slid off the remains of the bolts,leaving a few inches sticking out of the head--sometimes a hammer is used to bust up the remains of the manifold --once the manifold is off the shanks of the bolts they can often be removed with vise grips pretty easily,but usually one or two still break off in the head and have to be drilled out and re-tapped...