stripped and seized bolt - how to remove

[blabhern]

Hey all:

We've been working on a friends vehicle trying to remove the transmission fill bolt. It is seized and the head is now stripped from pipe wrenches, vise grips and the like. I believe the next option is to try to heat it up and see if it will loosen.

I've got an oxyacetylene wleder which I will be using. What I'd like to get from anyone out there is what is the proper procedure to use. I've never had to do this before (knock on wood) so it will be my first attempt. I will accept any comments, suggestions, safety precautions, etc.

Thanks in advance.

FYI-the vehicle is an 87 F**d Bronco II with a manual tranny. Yes I've told him to get rid of it, but it's got "sentimental value". [img]images/graemlins/laugh.gif[/img] [img]images/graemlins/laugh.gif[/img]

Spray on a little PB blaster before you heat it as for what to get on the end of the bolt im not sure..

[4x4mike]

I would try to cut a noch in the top or side of the bolt and use an air hammer to at least loosen it. I say at least because the hammer can cut the bolt head off.

Craftsman has these little jobbers that go over the stripped bolt and attach to a ratchet. I have heard that they work very well but are expensive. If you strip bolts often they maybe worth the price.
Michael

[wrath]

Heat up the case around the bolt, not the bolt. The idea is to get the case to expand around the bolt and hope the changing sizes will break it loose. If you just put the heat on the bolt it'll try to expand in the hole. You have to be very careful not to get it too hot if it is an aluminum case.

[c_rock]

A screw extractor may work. It has reverse threads on it, with a head for a wrench. You drill a hole into the bolt, then thread the extractor into it. As you thread it in, it will start to turn the bolt. I have a Craftsman set I got about 10 years ago, and it works pretty good.

[blabhern]

Thanks for the ideas and comments. I will tackle it today and will probably have to try all of the above. I was a little leary of heating up the tranny but it sounds like it will be ok. I'll let you know how it goes.

I really don't know what I will use to grab the bolt but I like the idea of cutting into it or trying the new sockets designed for stripped bolts.

you can take an air cutoff wheel or dremel to cut a slot in it and use a big flat blade screwdriver to get some torque on it. ive always read you want to heat the bolt directly. this way, the bolt will expand slightly and when it cools, it will contract and break the rust or corrosion causing it to seize.

at very worst, start with a 1/4" drill bit and work your way up to bigger bits, drilling all the way through the plug. once you get a hole big enough, you can use an awl to tap the remaining part out.