Rear brake pipe flexi to cylinder

Mot advisary to renew rear brake pipes. The short ones between flexi pipe and brake cylinder. Measured them up and found that the union on the cylinder I could get a 11mm spanner on but the union onto the flexi pipe it was a 10mm. That was the same for both sides.Whats going on. I thought that both threads were 10mm and that the unions would be same size spanner. Any input appreciated.

Neilc

The threads are 10mm both ends. Oddly the spanner size is different?

Don't forget that the flares are:

Wheel cylinder-normal single flare
Flex hose- Double flare.

The same nuts are used for both ends (M10 X 1,00 pitch) male thread.

No idea why the spanner size is different

The pipe in qestion has male unions both ends so won't the flares be double or have I got it wrong. I havn't got it off yet as don't want to start without correct kit because the way they look I think I will cut pipe and use socket.

Neilc

The male nuts are the same both ends but the flare on the pipe is different on the end that goes to the hose.

When I did mine a couple of months ago, the nuts were well and truly corroded into the wheel cylinder (Both sides) and I couldn't slacken them off. Try and slacken them off before actually starting the job, and if needs be, buy new cylinders prior to doing the job proper...they are cheap enough.

Thanks all for replies. I will follow your advice.
Thanks again

.

Neilc