Prickly_buzz

Was replacing my pads and discs this morning and all was well untill i went to re-fit the nearside caliper, the lower caliper bolt wouldnt tighten so i took it all spart again and found that there is little to no thread left on the knuckle itself....



I might add this car is on its last legs, i had to the brakes as they are metal to metal! So is there a quick fix if I said the bolt never needs to come out again?! I Chemical metal man enough?
It does screw in it just doesn't allow me to tighten it fully. Its not like theres a huge force pulling it out as it obviously mounted horizontally and braking would only force it vertiaclly (if that makes sense)

HELP!!!

tones61

loctite,
or if there is room,a longer bolt with a locknut on the back,

Prickly_buzz

Not sure if there's enough room for a nut on the back to be fair.
If loctite would work then couldnt chemical metal? I mean its never gotta be able to come out again!

Cossy Mike

iTrader: (4)

Drill it out and retap it the next size up?

costina

iTrader: (1)

Helicoil job done. Its M10 x 1.5.

Do not use loctite or chemical metal to repair a thread on such an important component.

Prickly_buzz

So is that the original bolt size? If so is it going to be possible to re-thread it as it is?

costina

iTrader: (1)

Yes im sure it is. But to be sure i can check.tomorrow for ya. As ive just fitted painted hubs on mine and i cleaned threads out.

Prickly_buzz

Lovely, would appreciate that as I need to go and get myself a tap and die set tomorrow, from what I've found looks like I need an 8.5mm tap drill?

costina

iTrader: (1)

What car? Tapping out will be no good imo helicoil or as said drill it out bigger and nut and bolt it which will be your cheapest option.

Prickly_buzz

It's a 2001 1.6 focus.
Not 100% I'd get a nut in there to be honest.

RichieST

iTrader: (2)

Nut and bolt it. I did that when I snapped off a pinch bolt on the top of a knuckle once. At least you won't have to spend hours drilling the bastard out like I did!

Prickly_buzz

Would this cause an issue with the caliper not being able to slide on the bolt?

Prickly_buzz

Just read that the torque setting for the caliper bolts is only 21lbft, with this in mind am I right in saying it doesn't really take a lot of strain etc?
I'm not trying to bodge here but if half the thread is there and I can wind the bolt in all the way, couldn't I just weld or chemical metal it in permanently,I'm sure this would suffice? (I'm starting to worry how im getting to work monday morning tbh)

RichieST

iTrader: (2)

I didn't see the bit where you said it was a focus, the caliper on these bolts straight to the knuckle with no carrier. So it probably wouldn't be the best idea to nut and bolt because as you say, it would lock the caliper solid.


I think either a helicoil or a second hand knuckle is going to be your only answer.