Stripped caliper bolt

[TheJMFC]

As the title suggests, I have a stripped out caliper bolt on my '93.

Is there any chance that an oversized caliper bolt exists for this application? A quick googling turned up nothing.

Otherwise, any suggestions? I have some ideas, but none are fun/easy.

[harofreak00]

Is the bolt or the bracket stripped?

I can get you the bolt if you want.

[TheJMFC]

Sorry, I should have specified. It's the knuckle that's stripped, save for about 1.5 threads at the end that the stock bolt doesn't quite catch.

Nah, the bolt would have been too easy. Thanks though.

[Archon]

You could try the Permatex stripped thread repair kit
http://www.acehardware.com/sm-permatex- ... 95869.html
It says that it will hold up to 128 ft.lbs. I haven't used it on anything that requires that much force, but it has worked well on stripped threads on a small air compressor. I don't know if you would want to try it on something as critical as brake parts.

Another option is a HeliCoil insert.
http://www.emhart.com/products/helicoil ... FQodZmD12A

Other options are: replace the knuckle; buy a longer bolt and put a nut on the other end, if there is enough room, and try tapping new threads for a slightly larger bolt, like metric vs. SAE.

[Bugsi]

Personally, I'd replace the knuckle. Fix it properly the first time and move on.

[TheJMFC]

Thanks for the suggestions.

I'd go for the knuckle as a last resort, but don't care to do an alignment at this time if I can help it.

Spending money on this car at all is hard to justify. The bulk of the front suspension is worn out, and even if I got around to replacing that, it's got the transmission "morning sickness" creeping into play. The $50 it cost me to turn rotors and buy pads was pushing what I could justify in the first place. I'm hoping to mostly just limp it through the winter reasonably well, and dump it for something fresher come spring. Just so you know where I'm coming from as far as how much, how correctly, I want to fix this.

I have seen that permatex kit, but I questioned whether or not it's temperature limit of 300 degrees would be safe, only about 1/2" from the rotor? Otherwise, I'd say it's a great idea.

Meanwhile, I'm probably leaning toward a slightly larger size bolt (standard or metric, whatever it's currently not).

I suppose I should disassemble the other side, just to see what else I break before I go parts shopping. I might need more stuff...

[bill buttermore]

If it is like many caliper bolts, you may find it is a really oddball thread size, like 9mm. Really hard to deal with. If so, I vote for a junkyard knuckle.

[TheJMFC]

It was odd, 11mm if it was metric.

Thankfully, I was able to get it together.

The stock bolts don't take full advantage of the hole depth, so while two of my holes were quite stripped to about 3/4 depth, I still had a few good threads at the end. On top of that, some of the strippage was actually on the bolts themselves, too. So, even where the holes were stripped, it wasn't completely gone. Mostly, but not completely.

So, I made myself a thread chaser out of one of the old, semi-stripped bolts, by filing down the last 3-4 threads, and cutting two grooves into the sides of the bolt with a Dremel, like a somewhat crude tap. It worked well enough to clean out the accumulated rust and brake dust from the remaining good threads. Then I picked up a new set of replacement caliper bolts. I hoped that the bolts would simply be longer, but instead I had to remove some material from the sleeves to allow the bolt to use all of the available threads. The overall length doesn't seem critical. Finally, I put it all together, using some blue loctite on the two that I didn't quite dare to torque down as much as I normally would. I still got them fairly tight, but I didn't want to push my luck any more. Fortunately, the two stripped holes are on opposite sides of the car, so both sides have at least one more solid bolt.

I had one very nervous moment when I went to test-drive it. It made this horrible grinding-scraping noise as I backed it up. Then I realized that I'd set the car down without removing the plastic pail I'd been using to support the caliper while I worked, and it was being crushed and dragged. I felt a little careless, but quite glad it wasn't anything seriously wrong.

The brakes feel good now. I'm pleasantly surprised, since I wasn't certain if the vibrations I was getting were only from the warped rotors, or if my drums needed attention as well.

Thanks again for all the suggestions and help.