I've sheared the head of the bleed nipple clean off from a brake caliper. You can see it in photo below (sry for poor quality), at the bottom of the brake.
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Any ideas on getting the body of the bolt out? It's clean level with the body of the caliper so you cannae grab it with pliers or such like.
If its not leaking, then its still usable, if you try and get the broken bit out by drilling or using an Easy-out you risk damaging the caliper, then its new caliper time. I'd probably just go for a new caliper rather than waste time trying to get the broken bit out, and next time try not to be so ham fisted. 😉
My first attempt would be to find a bolt you can fit in the hole. Superglue it in and see if that gives you enough purchase to get the nipple out.
I had a similar thing happen and went straight for the easy-out. It deformed the nipple outwards, damaging the caliper. However that one sheared when trying to undo it - it was corroded in. I had to drill it out in the end.
I assume your one sheared because you are a ham fisted goon 🙂 and were in the proces of overtightening it. In which case it will probably not be as stuck as mine was, so glue/easy out methods might work.
And dibbs - going straight to buying a new one!? Where's the fun in that? 🙂
EDIT: forgot to mention, if youre in a hurry just bleed it using the banjo bolt and fix the nipple later!
Where's the fun in that?
I've spent more than 35 years fixing broken stuff, and I'm afraid the novelties worn off 🙄
I've spent more than 35 years fixing broken stuff, and I'm afraid the novelties worn off
Fair doo's grandad!
Thks for the replies - it was a cack-handed performance that sheared it, no doubt. It's the brake on my wife's bike, which I've already replaced with a hand-me-down from one of mine, so it's not critical to fix to get out on the trail or anything. I'm just seeing if I can sort it or whether it gets lashed to the back of the shed.
When you drill it, is the idea that you just pulverise the bolt into a tiny pieces, whilst simultaneously trying not to damage the threads / housing?
If you have to resort to drilling it, the idea is to drill it with bits of slowly increasing size until the body of the nipple has almost been drilled completely away.
This might loosen it off enough that you can stick a needle in and unscrew it at this stage, or you might need to peel all the threads out individually.
Drilling it would be my last option on a bleed nipple because of the filings going in to the caliper, not good! Drilling will also knacker the threads which means helicoil or tapping a larger thread and sourcing the relevant larger bleed nipple. Try the easyouts first with loads of wd40 but remember not to do them up to tight or they will split the caliper as mentioned above or as previously mentioned superglue/arradite a bolt in. Aluminium and steel don't mix they oxidize and seize the threads, such a pain in the a*s!
See if you can find a torx drive bit and gently tap it into the small hole where it has broken off and see if it will un-do.Pour hot water onto the caliper near where it is this sometimes helps.