[xkeots]

I have one center bolt on each side of my exhaust manifolds on my 67 GTO 400 Motor that I cannot remove. I bought an broken bolt/head extractor kit but all it did was shave the metal on the head and not grab it.
The points of the heads are rounded now on both.
Should I
#1 heat the bolt?
#2 Hand file the flat spots so I can get a boxed or a socket on it?
#3 MIG weld a new nut on top of the old head then get my oxy/aceteline and heat the bolt and smack it with a hammer to loosen the rust on the threads?. I wish I could get Kroil or PB in there.
I do not want to snap the bolt.
All the others came out with a little back and forth play.
Any suggestions wanted.

Thanks
Jax
1967 GTO Convertible.

[Andre]

Whichever method you choose, I have found that applying clockwise torque first, will often make it turn easier when your try to turn it counterclockwise. I learned this from the old school guys.

[GT182]

Run the engine and get the manifolds and heads hot, or use a torch to heat them after you mig weld a nut to the bolts or file them to get a socket on them.

[Old Blue 66]

Originally Posted by Andre

Whichever method you choose, I have found that applying clockwise torque first, will often make it turn easier when your try to turn it counterclockwise. I learned this from the old school guys.

This works a lot. I also found that a good penetrating oil sprayed on many many times over they course of a couple of days works too. When we took off the old exhaust manifold off my old motor, I did this over the course of a week and they all came off with ease.

[carcrazy]

If you can get at them you can also tap with a hammer. This will sometimes loosen them up enough. If that doesn't help break out the torch (very carefully).

[jd66]

If you access to an oxygen- acetylene torch cut the head off the bolt and pull the manifold back , usually the bolts come right out of the heads then. jd grim 66 gto

[GT182]

Don't try and remove them with cold heads. Get the engine up to temperature first and work the bolts back and forth to free them up. When you put it back together, use never seize on the bolts so you don't have the same problem later on..... if you need to pull the manifolds again.

[1966geeto]

Originally Posted by jd66

If you access to an oxygen- acetylene torch cut the head off the bolt and pull the manifold back , usually the bolts come right out of the heads then. jd grim 66 gto

I would try option 3 if you think you can get another nut welded to it if not follow JD's advice you should be able to drop the manifold and gain access to the stud heat it up after soaking it try reverse rotation first then back it out I have had success getting the manifold as far away from the head as you can the cut the bolt flush with the manifold nut the head the manifold should come out leaving you an inch or so of stud left to work with.

[67ramairowner]

If you can get it moving clockwise even a bit try alternating clockwise counterclockwise clockwise. Increase the number of degrees you rotate the bolt with each clockwise, counterclockwise, clockwise cycle. Once it starts to move it gets easier..breaking the grip on the treads that is now locking things up is the start.

[Goatracer1]

The heads rust to the manifold not the bolts to the head. If you can get the heads off the manifolds will come right off and the bolts will unscrew like jd66 said.

[JohnS66GTO]

Originally Posted by Goatracer1

The heads rust to the manifold not the bolts to the head. If you can get the heads off the manifolds will come right off and the bolts will unscrew like jd66 said.

Could be rusted to one or both. I've had very good luck smacking the top of the bolt head with a ball-peen hammer a few (or more) times before putting torque on them. Taken out many exhaust manifold bolts this way that the "experts" said would never come out without a torch or breakage.

Take your time, be patient, and walk away for a while if you're getting frustrated. Do everything you can to keep from twisting them off. I feel your pain... and wish you luck.

John