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Disconnecting brake pipes for a while...
David Jenkins - 11/10/12 at 02:47 PM

When I do my back axle bearing & drum brake cylinder I will need to disconnect the brake pipe for a couple of days - I want to repaint the back plate while it's off the axle, where the brake fluid has stripped the paint off.

Now I know the trick about fixing some plastic over the top of the master cylinder so that it's air-tight, to reduce the loss of fluid there.

I can't clamp a flexible hose, as the only one that's in this circuit is a braided pipe.

Does it sound reasonable to push flexible hose over the brake pipe flare, and put a bung in the other end of the hose?

And before anyone says it - I know I'll lose some fluid when I do this, and that I'll have to bleed the rear circuit when I've finished.

Or does anyone have an alternative method they like to use?

mookaloid - 11/10/12 at 02:54 PM

How about a spare brake pipe fitting with a suitable size ball bearing to seat on the flare?

mcerd1 - 11/10/12 at 02:59 PM

quote:
Originally posted by mookaloid
How about a spare brake pipe fitting with a suitable size ball bearing to seat on the flare?


^^ thats what me and my dad always use

after 40+ years working on them my dad has quite a collection of old unions blocked off with either ball bearings or short bits of brake pipe folded over

britishtrident - 11/10/12 at 03:06 PM

Recently changing the subframe in a tintop I had the same problem, the solution was standard female to female Brake pipe joiner fitting with a bleed nipple screwed in one end. It was so handy I now keep a couple in my brake bits tool box.

BRAKE PIPE JOINER 2 WAY FEMALE CONNECTOR 10 X 1MM PK 5 | eBay

owelly - 11/10/12 at 03:06 PM

I have a few bits of brake pipe with the ends flattened and folded or soldered with the corresponding fittings, but I also use the '6mm bolt in the end of a bit of rubber tube method' too.

ChrisW - 11/10/12 at 03:10 PM

quote:
Originally posted by David Jenkins
I can't clamp a flexible hose, as the only one that's in this circuit is a braided pipe.


Why can't you clamp the braided hose? It won't affect it to be flattened; just make sure whatever you use doesn't damage the braid.

Chris

designer - 11/10/12 at 03:12 PM

I use golf tees to block brake pipes when I work on them.

Slimy38 - 11/10/12 at 03:15 PM

quote:
Originally posted by designer
I use golf tees to block brake pipes when I work on them.


+1 to that.

David Jenkins - 11/10/12 at 03:18 PM

quote:
Originally posted by ChrisW
quote:
Originally posted by David Jenkins
I can't clamp a flexible hose, as the only one that's in this circuit is a braided pipe.


Why can't you clamp the braided hose? It won't affect it to be flattened; just make sure whatever you use doesn't damage the braid.

Chris


It all depends whether the hose has a teflon tube inside - that type can't be squashed without breaking it. I think my hoses are that sort.

ChrisW - 11/10/12 at 03:19 PM

quote:
Originally posted by David Jenkins
quote:
Originally posted by ChrisW
quote:
Originally posted by David Jenkins
I can't clamp a flexible hose, as the only one that's in this circuit is a braided pipe.


Why can't you clamp the braided hose? It won't affect it to be flattened; just make sure whatever you use doesn't damage the braid.

Chris


It all depends whether the hose has a teflon tube inside - that type can't be squashed without breaking it. I think my hoses are that sort.


That's a new one on me! I've always just carefully clamped them. Never had a problem, but I guess I could have just been lucky!

Chris

David Jenkins - 11/10/12 at 03:20 PM

quote:
Originally posted by britishtrident
Recently changing the subframe in a tintop I had the same problem, the solution was standard female to female Brake pipe joiner fitting with a bleed nipple screwed in one end. It was so handy I now keep a couple in my brake bits tool box.



I like that idea...

Peteff - 11/10/12 at 05:40 PM

Take the cap off the master cylinder and put some cling film under it as well. If air can't get in fluid doesn't drip as much.

David Jenkins - 11/10/12 at 05:45 PM

quote:
Originally posted by Peteff
Take the cap off the master cylinder and put some cling film under it as well. If air can't get in fluid doesn't drip as much.


I said that in my original post!

In my case, it'll be a nitrile glove stretched over the top and held on with a rubber band...

Peteff - 12/10/12 at 08:46 AM

Sorry I only read the title I use a crimped piece of copper pipe in a union same as all the others and it works for me.

aeromanboeing - 16/10/12 at 08:13 PM

I cant believe some of the dodgy things I read on this forum. Clamping off a braided line, Have you no brains. You crush the teflon inner hose and the the stainless braid, Ok to clamp a rubber hose but then you bruise it anyway. Why not let the fluid drain out and replace it with new anyway. You should do it regularly and anyway and you will need to bleed the system . If you cant afford new fluid you shouldnt be on the road anyway.OMG

mcerd1 - 16/10/12 at 09:10 PM

^^^ steady on there
i happen to agree that clamping any kind of flexi is a bad idea in the long term, but you'd have to be crazy to let a brake system totaly drain on any road car (race cars are a different story)

its much harder to blead a dry system, if you block off the ends off the pipes so you save most of the fluid it'll be much easier to blead

and when you blead it you'll flush 99% of the old fluid out anyway so whats the problem ?

[Edited on 16/10/2012 by mcerd1]