I tried Welding a nut to it and that Just broke it off futher. I'm down to about a 1/4 inch of threads sticking out. I didn't try heating the surface. I'm Afraid to damage the Head.

Whats your ideas????

 

what engine? what head material?

 

is the manifold off?if so spray it with pb blaster,let it soak for a while ,then spray it again. you can apply a little heat, but not much.put a pair of vice grips on it very tight. IF it loosens, tighten it back, then loosen it again(it should get easier to move) loosen a little tighten a little until it comes out,later jimmy

 

They are the original Cast Heads. I do have the Manifold off. I've been Soaking it With Gibbs. Trying everything.

 

Left hand twist drill. If you do not have a small angle drill motor (like a Sioux or Wen) you may have to remove the head to remove the stud. It's only 17 more bolts.

 

Grind or file the bolt head absolutely flat; mark the EXACT center of it CAREFULLY and ACCURATELY with a center punch; drill with a 1/16" drill, then 1/8" drill, then 3/16" drill, etc. until no bolt remains, and the correct size for a thread insert is reached; install thread insert.

 

soak it with the lube, get a hold of it well and tighten it a bit, then loosen it and tighten it like 1fastam said, then use a thread chaser and find a new bolt, dont be hasty with it or you'll just screw yourself

 

May have to take it to a machine shop and have them do it. You're still "lucky", my bolt broke flush with the head, no one in this part of town could do it, so I said to hell with it, and just grabbed another engine head.

 

What are you trying to do?

 

When that happens to me, I grind them flat, then center punch and drill incrementally as someone above said. When there is just a shell of the old bolt left I use a sharp chisle to cave it in on itself and then needle nose pliers to work it out. I'm pretty good at it now.

 

I've had good luck doing the centerpunch and drill in just about 3/8' or so and then weld a nut to the bolt piece welding the hole you just drilled back closed. when the weld cools all the way (never quench) it will usually shrink in the hole some and then I soak it with PB and work it back and forth until it loosens. Use a MIG welder and crank it up high and slow the wire down so you get a good burn into the bolt and the nut. Has to be clean though and you already know what happens if you drill the hole off center!!!