broke water pump bolt

[5litreford]

I broke the bolt head off a long bolt while removing my water pump. I got the rest of the bolts out and the water pump off. I've got about a half inch of unthreaded stud sticking out. I've been spraying it with PB Blaster for the last 5 days. It won't budge. I've heated it up the best I could with a mini torch, no budge. I've hammered on it every day. I bought 2 special tools, neither could get it to move. I bought a new pair of vice grips. It got a good hold but wouldn't turn. I think the bolt will break off if I torque much more.
I'm at the point where i don't think it's coming loose, ever! I'm going to look for someone local who can weld a threaded stud onto it so I can just use a nut to tighten the new pump down. But, you can only get half way around the stud because it's about an inch away from a large bracket(that holds many things on).
Anyone have any other useful methods/ideas?
Also, to make things worse, I put a gouge into the pump mounting surface. It must be aluminum.

 

[bluesman2333]

I assume that the broken bolt is in the engine block? I have had success drilling bolts out in the past. You can buy a drill bit smaller than the bolt and drill in whatever the depth of the bolt is. I always use a very small drill bit and a center punch to get a pilot hole exactly in the center of the bolt first. After the bolt is drilled out, you can use an easy-out or just re-tap it if the drill size is the same as the tap drill size for that bolt. You can also use a thread repair kit if all else fails. Here is a link to what I am talking about. http://www.asashop.org/autoinc/may2003/techtotech.htm

 

[5litreford]

Yes, it's in the block.
I don't really know how long the bolt is, but I believe it's probably 5 inches.
I don't think that i can drill in 5" with a hand held drill and be centered all the way.
And I think an easy out will snap in half if I try that.
Do you see any drawback in leaving the bolt in and welding a threaded stud onto it? Other than filing the weld down so the new pump will fit over it.

 

[bluesman2333]

I'm guessing the bolt is in only about 3/4 of an inch. I've not had a water pump go out on a 4.0 yet, but if it is like other cars, that's all it is.

 

[chriswells78]

Let me guess, passenger side with a 1.5" threaded stud coming from it? I had to cut the bolt head off at the ear on the old water pump. Then in trying to get the old water pump off, I broke the ear on the WP where the bolt went through and was left with a bolt nub sticking out. I had to put vice grips on that nub sticking out with some PB blaster help. After much cussing and swearing, I got it out with the vice grips. When I replaced the WP, I used all stainless bolts where I could.