Brake Pipe Union Size

So today I thought I would fit my extended brake pipes. I went for the Goodridge from JimnyBits as they were in stock and a 7 day wait straight from Goodridge.

Anyway, I started on the front (I know some say front extended pipes are not needed, I did double check with Martin). But decided to fit them anyway, as the pipes came as a set of 4 and ARB recommend fitting them as part of the OME kit. not sure why there is a difference in opinion?

So my problem was the top union, it would not screw into the new brake pipe! As soon as the thread engaged it was solid, compared to the original pipe you could get 2 to 3 easy turns by hand. I did try the other three pipes on the union, all with the same result. Could I have got a bad batch?

Does anyone know what size thread it is, as I am very tempted to just buy a new union and try it in the Goodridge pipes, and in the event they are replaced I will want to check them first. It's not ideal finding out when you have already attached the new pipe to the caliper with the banjo.

So for now I have refitted the original pipe and bled the caliper.

Soeley the most common Modern metric sizes of brake unions are M10 & M12.

I Think M10's are available in two thread pitch sizes M10 X1.0/1.25.

M12's are available in predominantly one size M12 X 1.0.

I think it's quite unlikely that the JIM features imperial brake fittings. But the most common imperial size is 3/8 24tpi (threads per inch)

3/8's and M10 brake fittings are the two most commonly mixed up. You'd end up 'locked' after one thread turn which does sound similar to the issue your having... Do you have a set of vernier callipers? Best shout is to measure the threaded male union to determine what type of fitting you require (metric/imperial). Are the Goodridge lines marked up with any sort of identification/specification? There's no real easy way to measure the new female union.. Unless you had some spare brake fittings to hand.

Sorry I couldn't be more help!

This link is handy if you're trying to measure your thread size and pitch. www.hoseandfittingsetc.com/our-blog/bid/...tion-for-Brake-Lines

10mm x 1mm sounds about right then. I did measure the union with a micrometer. It came in at 0.389" and 26 tpi on my thread gauge. So 10x1 matches. It's not a normal standard thread then is it, as 10mm would normally be x1.5 for course and x1.25 for a fine thread.

M10 x 1.0 is pretty common from my understanding. Readily available size when looking at standard off the shelf brake fittings.

So you're saying the Rigid pipe male union is M10 x1.0? and the Goodridge female union isn't a good match? Pretty disappointing result from such a large company.

www.demon-tweeks.com/automec-male-fittin...ALw_wcB&gclsrc=aw.ds

No eBay APP ID and/or Cert ID defined in Kunena configurationLess than ideal, but as you've got the parts already - might be worth running a M10x1.0 tap down the female fittings. (If I've understood you correctly)

I did think of that, I will have to see if I have a tap that size. But first I might try a new union just to make sure.