Brake pipes, 140

I’m getting ready to start the plumbing job on my '55 140DHC. Am I correct in thinking that the entire system comprises 1/4" pipework? Wow - that’s going to be fun to flare and bend, I think.

I do have a disc front conversion kit, but am toying with the idea of starting off with the drums and switching to the discs if the drums don’t give full confidence. I think the kit uses 3/16" pipe, but it’s designed to work with the 1/4" in the rest of the system, I would think.

My 140 FHC has/did have 1/4" piping throughout, though I plan on using cunifer when the time comes…so much easier to flare and bend and somewhere around 90% as strong as steel.

I did my Mark V saloon a few of years ago with all cunifer (aka Kunifer, cupronickel etc), pretty similar to the XKs, much easier with the body off, and I had all the old steel lines to copy from, and saved all the end fittings. It was partly 3/16" where it served only one cylinder, and partly 1/4" where it served more than one. In any case, the threaded end fittings were my guide. It bends very nicely, and I used a bending tool only for small radius bends. It is imperative that you get the double flaring tool and practice with it following the instructions before trying a real flare end on your good tubing.
brake line flaring tools
double flare mandrels


I did some work on the rear brakes on my XK120 this past summer while the gearbox was off getting its innards sorted, mainly dealing with leaking rear wheel cylinders. Needless to say the brake lines and fittings (the originals as far as I know) were completely seized so I had to get replacements. These I secured from Automec in the UK (no connection) who proved to be very helpful in responding immediately to my email queries. The brass male unions were 7/16 x 20UNF 1/4 pipe. I picked up a coil of cunifer pipe locally here in Canada. I have a kit exactly the same as the one Rob depicted and double flaring brake lines is something I do once every 20 years or so (maybe!), however, the cunifer line is not only easy to bend, but also to flare. I was pleasantly surprised when it came to refilling the system and bleeding it that everything held with no leak problems. Certainly much easier to work with this line than the old steel ones and, if required, they can be taken apart at a later date.


Thanks all - I’m no stranger to making up and bending brake pipes - I must do 40-50 per year on average. I’ve had one of these for over 20 years now, and couldn’t live without it:

I also have a hand-held one for flaring pipes in situ. I only ever use Automec cunifer and agree it’s wonderful stuff. I tend to favour steel fittings over brass, which can deform quite a bit where they engage with the flare, but that’s a personal choice. However, apart from the occasional reservoir pipe, I’ve not done a whole car in 1/4" - only ever 3/16", hence my worry about bending. I also don’t have all the original pipework, as the car wasn’t complete - and the body is on and painted, which will make things a bit trickier, but not impossible as the system must have been designed to be serviced in situ.

Following on from Rob’s comments, does the 140 have a mix of sizes too? If so, will Viart be my friend here - or the factory parts book? Or, indeed, this forum?

I use the same Sykes-Pickavant flaring tool tool. So far, good results with Kunifer.

I think mine’s getting a bit tired now - it must have done at least 30 cars now all-in. An expensive piece of kit, but worth every penny. It does so much - brakes, clutch pipes, fuel lines - even the outer tubes the wiper rack runs in on most Brit cars. I’ve got the metric dies too, but they’re virtually unused.

edit - just gave it a check-over, and it’s actually as good as new. No softening of the die edges or punch profiles at all.