I did some work on my rear brakes yesterday to stop the moooing. Feel free to mock me cos I've made a catastrophic error - I've used red loctite (271) on the guide pin bolt instead of blue. Rest assured they are locked in place, permanently.

Before I stress myself out about this I want to look at the options. Red loctite melts at 250degC, so a blow torch may be my answer. I'm just worried about applying that amount of heat in the region of the brake calliper, especially considering the guide pins have rubber gaiters on them.

Advice would be appreciated

Thanks.

If your going for the heat have someone on the spanner at the ame time. Prob best to be hitting it with copper hammer as shocking as well as heat should get it to crack at a lower temp

Cheers. I also can't say that I used it sparingly, most of the thread area was coated. I really hope I can't sort this one out - otherwise it might be new calliper time

I take it the thread is at the head end of the bolt. If so heat on head and let it soak through. Id buy some new bolts ready to put it aswell

I take it the thread is at the head end of the bolt. If so heat on head and let it soak through. Id buy some new bolts ready to put it aswell

Not sure what you mean by "thread at head end of bolt". It's just a smallish bolt, 1/2 inch long, with a 13mm hex head. The thread is all the way along its length. I'm hoping heat air impact air tools will be the answer.

I've not had rear calipers off mine. So don't really know the setup properly. With you saying guide bolts o thought you meant the ones which the caliper slides on so would only have a short thread and a long hardened piece for that to happen.

Its the bolts labelled 1. They're about half inch long and threaded along their entire length. The biggest problem I see is the shallow head on the bolt which will be vulnerable under stress from impact sockets.

Edited 25 May, 201214 yr by piggoy

Fair play for admitting the mistake but I suspect with the amount of heat required to loosen the loctite will knacker anything rubber nearby. You weren't considering a brake upgrade at all were you ?

Fair play for admitting the mistake but I suspect with the amount of heat required to loosen the loctite will knacker anything rubber nearby. You weren't considering a brake upgrade at all were you ?

I hope the rubber gaiters are replaceable as a separate part. I contacted my local garage who do my MOTs and they say they should be able to undo the loctited bolts. I'm not in any rush, the pads are good for another few years yet.

Edited 25 May, 201214 yr by piggoy

I see what you mean now the set screw fits into the slider pin

If you end up needing new slider pins, bolts or gaskets, gaiters etc then give http://www.biggred.co.uk/ a shout. I found them very helpful when I needed new slider pins and a refurb kit (all the rubber bits).

HTH

Joe

Would it be sensible to attempt removal of the bolts sooner rather than later? The loctite is obviously already fully cured by now but I don't know whether or not it gets progressively worse over time.

As you have time on your side, have you contacted Loctite for advice?

3/8 air gun with impact extension will undo them.

I'd be surprised if you had a lot of trouble getting bolts out, the only issue will be making sure that you have a good grip on the head of the bolts as the head is quite "short" - its green Loctite that you want to watch out for especially on smaller bolts. Maybe look out for a hex ring spanner or hex socket instead of bi-hex.

Just give the bolt heads a couple of hits with a hammer, the longer they're left the harder they'll be to take out. I wouldn't use loctite on guide bolts tbh, it just clogs up the threads.

Just give the bolt heads a couple of hits with a hammer, the longer they're left the harder they'll be to take out. I wouldn't use loctite on guide bolts tbh, it just clogs up the threads.

Yes like forming a thread in the clearance hole that the bolt passes through, but, the new bolts come ready "fitted" with blue Loctite - and I think that places like Halfords sell "sticks" of thick Loctites, if buying the blue one then it could be used to prepare the used bolts in the same way as the new ones come.

Red Loctite attains full strength very quickly, so you may as well wait.

Threadlockers are thixotropic. In other words, a constant force over time will give reduced viscosity, but it is resistant to vibration or shock.

Using a hex socket on a breaker bar, apply a constant force and you may get it to move very slowly. Impact tools just won't work.

Raising the temperature also reduces the viscosity and a little bit of heat on the bolt will help. Too much and you will end up replacing the seals. You should also remember that brake fluid is flammable!

IIRC, you can get the guide pin protective sleeves as separate parts, but not the pins themselves (in which case you could have just ground the bolt heads off and replace the pins).