Broken caliper bolt
 

Well I was all set to change my brakes today. New pads, rotors, hardware and caliper bolts. It stared off good. Screws in the rotors came right out. Took off the pad sensors easy enough. Pin and clip out. Squeezed on pads and they came right out. Lower caliper bolt broke free no problem. Upper caliper bolt head broke right off. :mad:
I was able to get the caliper off of the bolt by tapping on it with a rubber mallet. I've been spraying PB blaster on it for a couple hours. The whole bolt minus the head is still in the hub. So I have about 3 inches to grab onto. So far I have tried vise grips, no luck. Also tried a pipe wrench, no dice. What would be my next move? Give the PB blaster more time? Heat? Help :eek:

Get some Kroil, and let it sit. It is the best penetrating oil you can buy. You may be able to use a stud extractor with a wobble extension and a large breaker bar. MAKE SURE the car is well supported on jack stands and blocked off.

Wouldn't it be easiest to just cut it off flush and drill it?

Heat would be the next step.

+1

I agree

Show a picture of the situation at hand

This is the bolt as it sits now.http://986forum.com/forums/uploads01/bolt1430014350.jpg

I have had very good luck with a HF Micro Torch that runs on butane in situations like this. Allows pinpoint heat in tight spaces. I would definitely try Kroil if you can get your hands on some.

Can you thread two nuts on it, jam them together, and the get on the bottom one and pull like #$%&?

I could most likely still thread some nuts on to it. I didn't mess the threads up too bad. I have a small map gas torch i could use. I was hoping the pb blaster would help after letting it soak overnight.

At this point i put the old rotor back on, wheel back on and it's sitting in the driveway until tomorrow. Thanks for all the tips so far.

yeah get a couple of nuts on there. if you need to run a die on the threads to get it cleaned up enough to do so, do it.

+1 on that

Well i couldn't find any place local that carries Kroil, so i soaked it with PB blaster. I will let it soak over night and start fresh in the morning. It seems really stuck in there. So with the two bolt system should i still use some heat as well? This was really the last thing i figured i needed to worry about. I was sure the rotor screws were going to give me the most trouble. Well maybe they will on the next three :barf:

+2 on heat and use the longest breaker bar you can come up with.

Get it as hot as you can - the remaining portion of the caliper bolt will start to glow red. I used a regular propane torch and you can get it hot enough with a little patience.

For a breaker bar, I use a 4-ft piece of 1" diameter Schedule K copper pipe with a 1/2" Craftsman 18" breaker bar slid into the end of the pipe.

Then crank on that beetch.

This is how I removed the exhaust bolts on my wife's BMW that broke off in a similar manner to your caliper bolts.

Heat, heat, heat (AND the PB soak).

Try heat on the bolt and/or the hub. If you use the 2 nut method, you need to turn the inside nut to try to loosen the bolt, of course. This will cause it to back against the outside nut and hold firm. I would go with vise grips rather than double nuts, but that will definitely bugger the threads and make the 2 nut method more difficult if you have to resort to that.

Last ditch would be to cut and drill out. I'm sure some PB, heat and vise grips (or double nut/breaker bar) will do it, though. I've always had the best luck with this method.

Ready this thread does not make me happy. Will be doing pad and rotor change here pretty soon. Guess I better order some caliper bolts too.

My method, which usually but not always works :)

Soak the bolt in penetrating oil for 24 hrs. Fill the cavity behind the bolt and gravity works. Tap on the bolt pretty hard with a hammer on a regular basis to loosen and allow penetrating oil to work. On day two, tap hard again and get a firm grip with vise grips. Start by turning it in the last direction it moved (clockwise) to break it free, and then spin it out counter clockwise. Often this will work without heat. If no-go, apply heat to the bolt with map gas torch and get her real hot. Often you will hear a ping when the bolt frees. Tap again with a hammer and back out with vise grips. If the penetrating oil works you will save the hub threads. Too much muscle too soon and the soft aluminum hub threads will strip out.

Good luck!

Sorry to read about the issue, but if another bolt breaks please let us know, so I can base how many I might need.

Thanks!:cheers:

Definately. Get a full set !!The older design bolts were hex heads, which of course can round out, the newer version is a large torx head.

What i find the best way of doing these is use a long breaker bar (2ft) pull it around so you have the tension wound up tight then 'snap' it around with the wrist to break it loose.

With the OP.. i'd try the two bolt method first, and get some heat on it before hand..

get heat on it then spray release oil on it, the heat helps the oil work down the thread, then get it hot again and try and work it out again with an extender on the spanner or socket. you may find it easier to work the both thread further in, before trying to turn it out.. Though if it's tight enough to break the head off without shifting you may be in for a fight with this bolt !!

What i have found with these bolts is that it is not the top of the head (shoulder) where they corrode up, it is the tip, so it will be the last half an inch as that is open and where moisture sets and causes the lovely steel/aluminium process that we all love (not).

Get the release oil on the end of the thread from underneath.

And if all fails.. dont be scared to take the hub carrier out and take it to an engineering place for them to get the bun guns on it.

All you'll have to do to get the hub carrier out is separate the ball joint, the track arm (if the ball joint on there is unlikely to shift (mine was ******************** - but was replacing the track rod ends anyway) and undo the bolt for the drop link bolt and tap that through (be prepared for more steel/alloy corrosion here (!) and tap the hub carrier down with a rubber mallet) i just did all this on mine as i stripped and repainted the struts as the surface corrosion was about to set in.

When you put the bolts back in, copper grease the bolts so they are not such a pain next time around!

Roger that, full set will be ordered.

Thanks for the info! :cheers:

Well I'm ready to go back at it. I'm first going to run to the hardware store for some nuts (for the 2 nut method). I filled up the hole in the back of the bolt with PB blaster around 5pm so by the time i get the wheel back off it will be around 18 hours. I'll see if there is any progress before i go with heat. I'll report back, wish me luck.

Luck!!!!!!!!

Heat, check. Nuts, check. PB blaster, check. Big ass breaker bar, check!!!! Good luck! And as others have said, tapping the bolt with a hammer may cause micro fractures in the rust and help break it free. It seems you have all bases covered.

Be sure to tap the bolt after the nuts are installed!

Good Luck :cheers:

Well it's still stuck in there. Should i put the nuts towards the hub or on the end of the bolt?

can you get some heat on it ? by some.. i mean enough to get it glowing red

preferably from inside the wheel arch out, so you dont burn up you sensor cables or the drop link bushes.

Yes I think can. I was hoping not to have to put a helicoil into the hub if I can help it. I may cut the lawn and let the PB blaster soak for a while. I can't just sit here and look at it lol.

Work on another set. See if another bolt breaks.

Kram that actually made me LOL! I was thinking about trying that. What ever you do DONT REUSE THE CALIPER BOLTS when you do your brake job. You can get a whole set for around $40 from ECS. I have all new ones, I just wish I could get them in :mad:

Already have them added to cart at ECS Tuning, with some more stuff I need. Still trying to figure out the pad/rotor combo I want to go with. I have to make a call to Centric Parts Monday to see if some rotors I'm looking at are High Carbon rotors or if some sites are listing them incorrectly.

Good Luck with the current broken bolt, hope the rest come out without issue. :cheers:

Well I can tell you this POS bolt isn't high carbon. Even with the two nuts on it, the bolt just seems to strip the threads. Even without a breaker bar, just a 19mm wrench I can see the nuts moving. The bolt wont move at all. At this point I'm thinking of putting it back together minus on caliper bolt and having it towed to my indie this week. The last thing I want to do is screw up drilling it out. I think I'd rather let him have a go at it. If he has to drill it out and put a helicoil in it I trust he would do a better job then me.

i feared this bolt wouldnt shift.. seeing as it was tight enough to shear the head !

you could just pull the hub carrier and take it to an engineering shop (or your indie - but they would probably do the same thing.) its a lot of bolt to drill out and it wont be done with a hand held drill. a metal shop engineering place would have the tooling to shift a stuck bolt.

just my 2 cents worth !

Heating is the best solution, and use/cut and form a piece of metal/aluminium sheet to protect other things like Bruce mentioned...

OK guys here is the status. Bolt still stuck. Filled up the hole on the back side of the bolt with PB blaster. Put old rotor back on. Put wheel back on. Letting it sit for at least another night. I did put some heat on it, but not enough to get it red hot. I was really hoping to save the threads in the hub. I'm thinking if i get everything red hot then the threads are shot.

I will call my indy in the am to see if he has any tips. I will probably let it sit with the PB blaster for a couple days as the weather will be crappy anyways. Right now the caliper is hanging behind the hub with some zip ties. The nuts are still on the bolt. After the weather clears up in a couple days I may give it one more try. Depending on what the indy says I may go with red hot heat. Or i may just tow it in later in the week. Any new tips or prayers are appreciated lol.

Weld an old socket onto it and use an impact wrench. :p

I feel for ya, buddy!

That's a good idea, as long as he has a really good impact gun.

No welder required though, according to this guy:

https://www.youtube.com/watch?v=PV5oLPLUzrM

Well I have an impact gun. Now I just need to take the battery out of the Boxster and my wifes car. The video makes it look easy enough, I think i'll give it a shot in the morning. What could possibly go wrong? :eek:

Just use some coat hangar wire for a rod. Make sure you hook the batteries up in series to get 24 volts! :D

I take no responsibility if you actually try this, btw. None. Zip. Nada. I'll put this on the same page as using ether to set your tires on the bead.

Be pretty cool if it worked though... Probably S.O.P. for the boiler banger.

Can you get a die grinder in there? In cases like this, when encountered in the past, I would grind two flat surfaces at the end of the bolt so I can get another wrench on it, then lots and lots of heat (as others have mentioned), breaker bar, and a hammer. I use the hammer on both the end of the bolt, and on the breaker bar as opposed to continuous, increasing pressure, in hopes of snap-breaking it free. Otherwise... new upright or machine shop...

Call a couple of local gun shops to see if they have Kroil. I am not saying it is magic, but I have always had better luck with Kroil over PB. I know you are trying everything you can, so I'm still wishing you luck