stuck caliper mounting bolt

[wrangler]

I am assuming that you are referring to this clip? This one just happens to be from a 65-73 Mustang.

[sugg578]

Ok on my gt all the bolts for the brakes are stuck. What size star thing did you all use. How did you all use a breaker bar I cant see any way to do it.

[jordan]

Originally Posted by sugg578 Ok on my gt all the bolts for the brakes are stuck. What size star thing did you all use. How did you all use a breaker bar I cant see any way to do it.

Umm you're not going to want to do that. Removing the star bolts would split the calipers in half revealing a very hard to source square shouldered seal that is not necessary when doing a common caliper rebuild. Also if you were determined to get into a situation with 2 halves of a caliper I would at least take the caliper off of the car.

[sugg578]

Ok thats what I wanted to do. So how would I do that.

[jordan]

Originally Posted by sugg578 Ok thats what I wanted to do. So how would I do that.

You remove the 2 caliper mounting bolts that is what this thread was started for. Additionally the brake line will have to be removed.

[jvandyke]

top bolt out, bottom one is just as stubborn, borrowed an electric impact wrench, can't get a good straight fit on the bolt head, didn't seem to do anything, heat then whacking the handle of the socket wrench with a sludge hammer got the top one. I'll revisit the bottom one later.
Took out pads, the font piston must be the culprit as that pad didn't want to come out. One bolt now stands in my way. Bad bolt, bad!

[jvandyke]

Got it here's the sure fire formula: heat, oil repeat, grunt gripe, pound, heat oil, pound, impact wrench swear, heat, then put 1/2 drive socket wrench pointing to the car's rear so handle up would be loosen, I put a scissor jack under the handle (any jack would do) and cranked it up slowly, stopping to wack on the socket wrench socket end with a hammer every so often and she gave it up without breaking, wow that was a pain.
I think if you skipped the oil, heat, pounding and time you'd probably just snap the bolt.

[Anonymous D]

Another alternative, to scouting around
and hoping you will find the correct length
metric bolt (at the correct grade),
is to simply call an Opel retailer and ASK
for one (!)

[Lindsay]

Months ago, I grunted and moaned trying to remove my (4) caliper, mounting bolts. After several dousings with PB Blaster, my long breaker bar with 6-point socket finally loosened all four bolts. Previous Owner had repair shop accomplish most of his repairs; Darn impact tools!

As the oil commercial shows; oil and water do not mix, but oil (grease) and blood does mix.

[namba209]

Originally Posted by Lindsay Months ago, I grunted and moaned trying to remove my (4) caliper, mounting bolts. After several dousings with PB Blaster, my long breaker bar with 6-point socket finally loosened all four bolts. Previous Owner had repair shop accomplish most of his repairs; Darn impact tools! As the oil commercial shows; oil and water do not mix, but oil (grease) and blood does mix.

Ahhh, another testament for using a torque wrench and aniti-sieze compound.

[Sparky73]

Are both bolts right handed thread or are they opposites of each other like some bolts on some vehicles? I know the austin healey I worked on even had the lug nuts left / right handed..

[namba209]

Sparky, they are all RH threads. The problem is the same as with the exhaust bolts, a little moisture, some heat, and they get rust welded together. Try the numerous types of rust penetrants, even the wax candle method. Heat, and maybe some direct blows to the head of the bolts can break them loose. One thing for sure, you don't want to use a long breaker bar, that will shear the bolts for sure. Time and Patience is where it's at. Be sure to use some anti-sieze compound on the bolts when you put them back together, and use the correct torque so it won't happen again.

[Lindsay]

Unless LH thread ...
**Righty Tighten**
**Lefty Loosen**

Tried Marshalls Hardware (San Diego) and McMaster (Internet) to locate M12 fine thread bolts that attach caliper to steering knuckle. I could not locate!
Ordered M12 coarse bolt with shank (not threaded to hex head) from McMaster (incorrect thread).

[Sparky73]

Well I used about a 1/2 a can of 'Liquid Wrench' and an Impact Wrench.. and the bolts came off like they weren't even stuck LOL

My method: For 4 days, I sprayed both bolts with Liquid Wrench, multiple times day.. anywhere from 3-8 times, depending on how busy I was. Used about a half a can total lol. Dad borrowed his good Impact Wrench from the shop, and just a few minutes ago, turned the wheel completely to get better access to the bolts. Pulled the trigger for not even a second, and the came loose.. and actually unscrewed them the rest of the way with my fingers!

I guess patience does pay off. Didn't break either of them, threads are all great, and the heads aren't stripped at all. So something is finally going right!

[2 Fast 4 U]

Originally Posted by namba209 ......insist on Grade 8 bolts in metric threads... Ron

I only know of grade 8.8 or is this only for Europe??

[RallyBob]

Originally Posted by 2 Fast 4 U I only know of grade 8.8 or is this only for Europe??

Different ratings. SAE grade 8 is similar to grade 12.9 metric fasteners.