union

[les]

I need to know if the brass union that is fitted to the rear of the master cylinder has a convex base or concave, like the brass unions fitted to the rear wheel cylinders that take the bleed nipples, can anyone tell me?

[alex_holden]

I think the banjo fittings on the master cylinder are the same as the ones on the rear slave cylinders.

[les]

Thanks Alex, in that case the end of the new brake pipe I have should be convex, which it isn't!

[alex_holden]

I've a feeling all the pipes in the kit I used had concave ends. I think the inside of the fitting is this sort of shape (cross-section through the mating face):

|/\ /\|

The convex pipe end mates with the outside of the ridge, but the tip of the bleed nipple mates with the inside. Don't take my word for it though as my memory is a bit hazy about this.

[bigginger]

The one at the rear of the M/C isn't a banjo fitting though, is it? I'm confused, but I'll have a look tomorrow, since I have a few out of cars with original pipes still attached.

[alex_holden]

The one at the rear of the M/C isn't a banjo fitting though, is it? I'm confused, but I'll have a look tomorrow, since I have a few out of cars with original pipes still attached.

It certainly is in the manual, and that's the way I did it when I put Fenchurch back together. The front brakes go into the banjo and the rears into the bolt.

I've just had a look at a spare banjo fitting and it has a convex cone inside, not exactly like the above representation, more like this:

Code: Select all

|           |
|   _   _   |
|  / | | \  |
|_/  | |  \_|

I don't have a spare bolt to check if that's the same shape inside, but I would imagine it is.

[les]

Thanks Alex, My fitting is as your first diagram, although not quite as defined. I thought/think as you do, that it seems to accomodate both pipe ends, but as your second post suggests that there are two different brass banjo seats, it looks as if I need to find one with the convex seat. I phoned esm today and they said that the bleed nipple unions and the m/c union use the same part. The short link pipe in the kit I bought ( the one linking the front cylinders) has convex ends all the rest have concave. I think the concave is known as a single flare and the convex a double.
The bolt is the same as your second diagram.(convex)

[bigginger]

Oh, and you're quite right about the banjo union of course. Didn't remove a pipe though, to much else to do

[les]

Didn't remove a pipe though, to much else to do

Go on remove it, I want to know the shape of the seat!
ps: to =too, I know you like your grammar right!

[bigginger]

OK, I will - and ta for the correction

[les]

many thanx!

[bigginger]

Damn - I took the pipe off the rear outlet today, and checked that (it seema to be a concave end and a single flare, though it's hard to be certain on a 40 year old pipe and a union you had to butcher to remove) but didn't look at the banjo union - poor memory...

[les]

Well thanks for doing it anyway, I've found one with a convex seat, will fit this tomorrow and then the brake pipe end will suit.