Seized Brake Caliper Mounting Bolt
 

I was performing the, usually, simple job of replacing my front rotors on my 97 base. The bottom mounting bolt came out just as expected, but the top bolt would not budge,that is until the head sheared off. Anyway, I removed the caliper and the rest of the bolt is still seized in the caliper housing. No sign of rust and it is currently soaking in blaster. Is this occurrence common?

Bradster

Yes - the guys in the UK (and anywhere else the weather is bad) have a real problem with the bolts corroding & snapping in the alloy housing....
After you remove the old bolt stub, remember to use anti-sieze lubricant paste on the threads of the new bolts - it will make future removal a lot easier.

Update:

After heating the mounting bolt, it turned with a pipe wrench about a turn and then sheared off again. There was more bolt to grab on to, so I reheated the bolt and turned it some more with the pipe wrench and a pipe. There is no rust or corrosion evident. I assume that, with almost no bolt to grab, I will now have to drill the bolt out being careful not to destroy the threads inside the strut, although I suspect that they must already be ruined.

Never heard of a bolt that would break free, turn, and then shear off twice more. Its almost as if the bolt and the mounting hole have merged and welded together on their own. I have owned a lot of cars and never seen anything like this. (Wish I had left the rotor on.) I believe I am the first to remove the mounting bolts.

Anyway, I just thought I would re-post to see if anyone had any other ideas. I am at a loss at his point. Replacing the strut over a mounting bolt seems like a bad dream. Obviously, even if I get the bolt out, the internal threads likely will be shot.

As always, thanks.

Bradster.

If you have access to a welder ( or someone with one ) , weld a nut or bolt to the stub thats left. It gives you something to grab, and heats the joint at the same time. It's worked for me.

bradster -

sorry to say it, but you'll likely never get the bolt out. the aluminum is galled & the threads are destroyed at this point. the safest / easiest bet is to source an upright from a wrecked car. they can be had on the cheap.

by the time you could even devise & implement a solution with your current upright, you will have spent more time & almost as much money as if you'd just replaced the upright.

I've had it happen twice and...
 

... was able to successfully remove the broken bolt by drilling it out.
I use successively larger LEFT-HAND drill bits.
Grainger has a nice set. They are expensive, though.
The trick is to start completely centered, so you'll need to carefully center-punch the broken bolt. You may need to file a flat spot if it's crooked.
Also, soak overnight with PB Blaster.
Once you start to see the threads, use a sharp pick and pick out the remnants.
Sometimes the action of the PB Blaster and the use of the left-handed bits will remove the broken bolt.
Happy Boxstering,
Pedro

You will get it!
 

Had the same thing happen, my buddy and I tried it all...PB Blaster, heat and when after 7 hours he broke 3 easy outs(heavy duty aircraft one) I was worried. The next day he went at it again with an easy out and various bits until success. I bought a heli-coil kit from a local auto parts store used one insert and sold the kit on ebay to recoup my money (kit was 90.00). No problems since, and I coated the bolts with anti-seize on the way back in!

Thanks all. Ended up buying a titanium pilot bit at Home Depot ($5.00), centered it, and using increasingly larger bits, removed the old bolt. Will have to use a helicoil though as the threads are now destroyed. Crazy that a 30 second job became an expensive 7 hour ordeal. Makes no sense.

Anyway, and as always, thanks for he suggestions and support.

Bradster