How to remove broken caliper bracket bolt?

[1 SX]

Long story short I upgraded the brakes rotors pads and was going to replace all the hardware/shoes in the parking brake system. I was going to work in steps, do all the brakes first then re-attack the rear parking brakes a day or two later.

So far so good but the last bolt of the job, a 14 mm caliper bracket bolt snapped as I was tightening it down … I could only think because I was getting tired and I decided to put a extension pipe on the tool and it gave me way too much leverage.

So as I stand now, I can’t get the rotor or caliper bracket off to replace the parking brake hardware and shoes because I can’t get the caliper bracket bolt out to remove the caliper and the bracket 😂

So what I’m asking is what would be the best possible attack on this without damaging any threads or the caliper bracket or anything like that?
I’m willing to buy an extractor set and drill bits and go to town, If that’s the best possible solution for this issue. What would you be doing in the situation? I have my local shop on call as a absolute worst case scenario.

Thanks!

 

[D60]

LH drill bits but in order to be sure you don't do anymore damage you'll likely want a custom bushing to keep your bit centered. I just make such things on my lathes.

edit: if it's a thru-hole you can probably get away with standard RH bits

 

[Trav]

You can get these at ACE hardware or possibly HD.

Bronze Bushing 6mm ID x 14mm OD (12 pack)

The 6mm bronze bushings are ideal for use with robotics design and competitions. As with the other Studica Robotics building components, it has the common hole pattern which makes it easy to connect to other structure with very little or no additional machining required. You can easily connect...

www.studica.com

 

[Rand]

The centered drillbit method might be a good start.
how I would proceed would depend on if you have ever used a tap and are confident using them if you mess up the threads.

I had the opposite problem the threads all fell out of the hole when I was tighting the bracket bolt.
we ended up drilling it a tiny amount larger then retapping for a slightly larger bolt.

At the time the bracket was dealer only with caliper purchase for $250+ and on backorder.\
and the aftermarket brackets that were available were brand specific and didnt fit oem caliper.

 

[Chris142]

I think that's a 10 mm bolt. A 14 mm bolt is a pretty big bolt.

 

[Trav]

12 and 14mm are the most common caliper bracket bolts.

 

[Hall]

I think that's a 10 mm bolt. A 14 mm bolt is a pretty big bolt.

Right or wrong, everyone tends to refer to a bolt's size based on the head (or tool that fits).

 

[1 SX]

Thank you for the replies I ordered The necessary supplies and I will attack this this weekend. I will keep you updated.

 

[JTK]

What vehicle? How bad is it to swap the whole knuckle?

 

[Rand]

What vehicle? How bad is it to swap the whole knuckle?

2009 kia maybe.

 

[slacktide_bitog]

Drill it out, order a new bracket, and of course new bolts.

 

[atikovi]

I can’t get the rotor or caliper bracket off to replace the parking brake hardware and shoes because I can’t get the caliper bracket bolt out to remove the caliper and the bracket 😂

If you take the other bolt out, can't you swing the caliper up enough to wiggle the rotor out? Or just cutoff wheel the bracket off? A new bracket is like $30 compared to a tow and repair bill.

 

[The Critic]

Right or wrong, everyone tends to refer to a bolt's size based on the head (or tool that fits).

Bolt Depot - Metric Bolt Head, Wrench Size, and Diameter Table

www.boltdepot.com

Best practice is to refer to bolt sizes by their diameter and thread pitch, not the head size.

Anyway, it looks like the bolt head snapped off and let the remainder inside the bracket. Depending on access, you might need to disassemble the rear suspension to gain enough room to drill/extract that bolt. Do you have a 90 deg drill?

 

[Hall]

Best practice is to refer to bolt sizes by their diameter and thread pitch, not the head size.

Know what you mean, but honestly, it really depends on the use-case.... In my previous life as a mechanical designer, yeah, I would put threaded holes in a part and spec it as "M8-1.25" and the BOM would say "M8-1.25 x 50". The CAD software would insert the fastener to the correct scale/size and I didn't need to know the head size (beyond making sure it fit).

When you're doing a brake job, you use a 17mm socket or wrench to remove the bracket fasteners and like above, you don't care that the fastener is M10-1.5.

 

[Astro14]

Know what you mean, but honestly, it really depends on the use-case.... In my previous life as a mechanical designer, yeah, I would put threaded holes in a part and spec it as "M8-1.25" and the BOM would say "M8-1.25 x 50". The CAD software would insert the fastener to the correct scale/size and I didn't need to know the head size (beyond making sure it fit).

When you're doing a brake job, you use a 17mm socket or wrench to remove the bracket fasteners and like above, you don't care that the fastener is M10-1.5.

Actually, I DO care that it’s a M10 1.5, and 8.8, or 10.9, or 12.9, because that, and not the head size, determines the torque.

This whole situation is the result of over torque, using a pipe.

Knowing how much torque to put on a particular sized bolt could’ve saved the OP a lot of heartache.

Bolts in my spare parts bins are sorted by thread size, not wrench size.

Just like a hardware store, or fastener store.

 

[CleanSump]

Best practice is to RTFM and use a torque wrench.

 

[Blueshound]

I know what I would be thinking: Maybe it really only needs one bolt . . .

 

[Astro14]

I know what I would be thinking: Maybe it really only needs one bolt . . .

I’m thinking it needs four NEW bolts. Two for each caliper.

If he grossly over torqued this one using a pipe, what are the odds that the other three haven’t been stretched?

 

[Blueshound]

I’m thinking it needs four NEW bolts. Two for each caliper.

If he grossly over torqued this one using a pipe, what are the odds that the other three haven’t been stretched?

Agree. In case anyone else missed it, I was joking.
OP, it's possible if you take the caliper, pads and the other bolt out you might be able to tap the bracket back far enough to get it off. That would make your job a lot easier, especially if there's a stub you can grab with vise grips.

 

[Hall]

and 8.8, or 10.9, or 12.9, because that, and not the head size, determines the torque.

No one brought that up (someone else brought up bolt head size and it went from there) and while those grade values have a meaning, the manufacturer comes up with the actual torque spec. Those grades determine the maximum torque that that fastener is rated for, not the torque for the application it's used on (though it won't or can't exceed that max value).