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Rear brake joint nut leaking, I think?

Posted: Sun Apr 29, 2012 5:34 pm
by oldgreyandslow
Got the fronts sorted and now trying to get the rears done and it sounds like there's an air leak at the joint.

The rear caliper has new seals and pistons and I have just fitted a HEL line, new washers at the MC end and the line just screws straight onto the joint, it was a bit of a sod to tighten but I'm pretty sure its OK

When bleeding through fluid, with air bubbles comes out of the bleed screw exactly as expected, tighten the screw with the lever down and when I release the lever there's a distinct sound of escaping air or fluid from around the joint.

I haven't chnaged the joint or sealing washer.

Is it likely to be the joint and washer that's the problem? If so the joint seems a very tight fit on the caliper I think getting it off will be a challenge, is there an easy way to check it's actually this and not something else causing the problem?

Any suggestions welcome

Thanks

Re: Rear brake joint nut leaking, I think?

Posted: Sun Apr 29, 2012 7:40 pm
by Deviant400
are you talking about where the brake line screws into the caliper , if this was a bitch to screw in then id be inclined to think the line may of had the wrong pitch of thread and possibly (worst case you may of cross threaded the caliper screwing it in ) i only say this as when overhauling my rear caliper shortly after i bought my nc the same happened to me , the pitch was correct but the connection on the end of the line was a bit crap and the thread was a bit mangled i ended up having to get another line and a second hand caliper :roll:

Re: Rear brake joint nut leaking, I think?

Posted: Sun Apr 29, 2012 8:04 pm
by oldgreyandslow
Deviant400 wrote:are you talking about where the brake line screws into the caliper , if this was a bitch to screw in then id be inclined to think the line may of had the wrong pitch of thread and possibly (worst case you may of cross threaded the caliper screwing it in ) i only say this as when overhauling my rear caliper shortly after i bought my nc the same happened to me , the pitch was correct but the connection on the end of the line was a bit crap and the thread was a bit mangled i ended up having to get another line and a second hand caliper :roll:
yes its where the new line screws in to the joint that screws into the caliper

Image

The caliper is not bolted to the bike in the photo above, but the new line is on the left and that screws in to the union which in turn is screwed into the caliper. Getting the line to fit to the union was difficult but I think the leak is either at the caliper join or actually at the nut which the line screws into, I just can't be sure and at £15 from david silver I'd like to be sure its faulty before buying one

Re: Rear brake joint nut leaking, I think?

Posted: Sun Apr 29, 2012 8:12 pm
by Deviant400
yeah i see , wouldnt know what to suggest then pal , i recently installed a brand new line and to be honest i think i just put my new line direct into the caliper and didnt use that bit

Re: Rear brake joint nut leaking, I think?

Posted: Mon Apr 30, 2012 4:47 am
by Neosophist
Put the line directly into the caliper.

Re: Rear brake joint nut leaking, I think?

Posted: Mon Apr 30, 2012 9:10 am
by oldgreyandslow
Neosophist wrote:Put the line directly into the caliper.
Great thanks, I'll give that a go.

Re: Rear brake joint nut leaking, I think?

Posted: Mon Apr 30, 2012 10:39 am
by Deviant400
you might have to be carfull that the line dont twist up though, the connection was fixed on my line and didnt rotate so you might have to take the banjo bolt out of the master cylinder to allow the line to rotate, i installed mine caliper end first then threaded it up over the chainguard and so on

Re: Rear brake joint nut leaking, I think?

Posted: Mon Apr 30, 2012 11:59 am
by oldgreyandslow
Deviant400 wrote:you might have to be carfull that the line dont twist up though, the connection was fixed on my line and didnt rotate so you might have to take the banjo bolt out of the master cylinder to allow the line to rotate, i installed mine caliper end first then threaded it up over the chainguard and so on
You're right my line is fixed too, I did fit it to the caliper end first and threaded it through when I fitted it originally. Good job the Hel kit comes with more than enough copper washers!

I'll get there in the end!

Re: Rear brake joint nut leaking, I think?

Posted: Mon Apr 30, 2012 3:16 pm
by Neosophist
Deviant400 wrote:you might have to be carfull that the line dont twist up though, the connection was fixed on my line and didnt rotate so you might have to take the banjo bolt out of the master cylinder to allow the line to rotate, i installed mine caliper end first then threaded it up over the chainguard and so on
Or you can take the rear caliper off to tighten it up.

Re: Rear brake joint nut leaking, I think?

Posted: Mon Apr 30, 2012 5:33 pm
by Deviant400
:plus: :grin: