bolt extraction

[rckracing88]

I am trying to remove a cylinder head, head bolt on an aluminum cyl. head.
The bolt is a break away bolt and has a flat slightly rounded head ,, like a bumper bolt. I am using a 80 amp campbell hasusfeld gasless flux core mig.
It has a high and low setting. I am having problems with penetration and getting a solid weld,, it wants to wad up and the nut will not hold before it breaks loose. The bolt is 70 to 75 ft. lbs. of torque.
Can anyone give me some insight on this,, or will this type of welder even accomplish what i am trying to do.
Thanks

 

[Porschemaniac]

From your description, I'm guessing the bolt has sheared?

I did have a similar problem myself on an old 2 stroke motorcycle. After a few failed attempts, I found the technique was to screw the nut on a couple of turns and then weld down into the 'we'll' the centre of the nut forms on top of the bolt.

This seems to concentrate the heat more effectively - the heat on the bolt should also help break it's bond on the thread.

When I did mine, I was using an old SIP 90 amp gasless - so about the same power as your welder.

Hope this helps.

Cheers,

Ian.

 

[rckracing88]

Thanks ian