minor emergency - please help

[Relfy]

Oh dear... I made another mistake.

I needed to change number two front wheel cylinder as its weeping quite a lot... only I've never done it before and when I went to get the copper hose off I turned the spanner ever so slightly - and broke it clean off the connector!

As the skies open and the lightning flashes across the sky - what should I do to stop the brake fluid dripping out? Bung it up with something?

In the longer term, how can I fix it? Is it just a case of pulling out the broken bit from the connector (there is a tiny bit sticking out which i might be able to grab with a long-nosed pliers) and jamming the end of the pipe in? (It is not warped atall)

Or do I need to get a new connector/copper pipe?

Or any other nifty solutions anyone can think of!!

Help would be much appreciated! Thanks in advance...

[alex_holden]

If I understand correctly, you've broken the end off the little pipe that links the two cylinders together. The ends need to be flared to make them seal, so you'll need a new one. Your friendly local garage ought to be able to make a replacement for you if you show them the broken one. The proper way to stop the fluid leaking out is to put a special hose clamp on the flexible hose, but I'm guessing you don't have one of those or you would have already used it. I'm kind of loath to suggest it, but I have in the past used a large toolmaker's clamp with chamfered edges, clamped lightly on the hose (obviously you don't want to clamp too hard and damage it).

[Relfy]

If I understand correctly, you've broken the end off the little pipe that links the two cylinders together. The ends need to be flared to make them seal, so you'll need a new one.

Yes that's right. Thanks. I dont understand the flaring the pipe bit though - how would you get it into the connector flared? Or does 'flare' mean something different to what I think it does...

I've managed to stop the dripping by forcing a very narrow bleed pipe over the end, folding it over and clamping that - should be ok until morning hopefully

Best way is to you need to make sure you have a replacement pipe before touching removing the wheel cylinder. The end of the pipe shearing is pretty common unless you are careful to avoid it.

- learnt that one now.

[Willie]

You have to give the two threaded connectors to the person making up the
new pipe, these are fitted to the pipe before the ends are flared. Take the old pipe with you so that they know the length to make up. Be very careful when
bending the new pipe and refitting to your car that the pipe does not foul the suspension on right or left full lock.

[Relfy]

OK Thanks Willie. I'll try and do that. Just a couple more questions - Do i have to find some suitable pipe or will a normal garage have some? And, when re-attaching it to the car, how do you tighten up the connectors without breaking the pipe again?

Thanks,

[Packedup]

Most motor factors can make pipes, but make sure they use the right ends! I say that because I had a pipe made up, and the fool that did it used a metric end... Which was just close enough to the correct imperial one to trick me into fitting it. Now have a master cylinder with decidedly dogdy thread (wasn't a Minor).

When fitting, I tend to push the pipe into the hole so it makes as good a contact as possible and also gives some free play on the union for lining/ tightening it up. The pipe shouldn't snap, and only went on yours cause it's old and corroded to the union. In future, try using a little plusgas and working the spanner to and fro a bit to break the seal before trying to undo properly!

On the bright side, it's much easier to remove the union from the cylinder now you can get a socket on it... ;)

[Relfy]

Most motor factors can make pipes, but make sure they use the right ends! I say that because I had a pipe made up, and the fool that did it used a metric end... Which was just close enough to the correct imperial one to trick me into fitting it. Now have a master cylinder with decidedly dogdy thread (wasn't a Minor).

OK, I'll watch for that. Thanks. I'd never have thought of that if you hadn't told me!

When fitting, I tend to push the pipe into the hole so it makes as good a contact as possible and also gives some free play on the union for lining/ tightening it up. The pipe shouldn't snap, and only went on yours cause it's old and corroded to the union. In future, try using a little plusgas and working the spanner to and fro a bit to break the seal before trying to undo properly!

Ok thanks. Actually I only turned the spanner a couple of mm and it went 'ping!' Oops.
I wasn't being very careful though and I hadn't read about it first, which I normally do.... Must learn: Less haste, more speed. Now I have to find a way of getting the broken end out of the union. Maybe the garage'll be able to do it... or cycle the 17 miles to Bull Motif and get another one before they shut at 12.30....

I've been doing a search (belatedly) about brakes on here now and copper washers come up a lot... am I supposed to know something about/ have some of them? Or is that just if I'm taking the cylinder apart or something like that?

On the bright side, it's much easier to remove the union from the cylinder now you can get a socket on it... ;)

[Packedup]

I'm trying to remember Minor pipework now - Isn't it about a 6 inch pipe from one cylinder to the other? And the end that's broke is in the cylinder you're replacing?

Take the pipe off (carefully!) the other cylinder, the ends will be the same. Go to local motor factors, pay about 3 quid for a new one with new ends, bend to fit (carefully again!) and voila!

Am I right in thinking original pipes are steel? Given the age it really wouldn't take much for a slighty poor one to simply snap, though when you want them to they simply corkscrew... If you don't see a gap/ sign of movement between union and pipe when undoing, work it back and forth and get some Plusgas (or WD if you really must) in there until the union moves freely and the pipe doesn't try to follow it. Fitting new is much easier, but unless a pipe is in need of replacing I try to save wherever possible and avoid forking out for yet more bits


One thing you might want to think about is a brake pipe spanner if you haven't already got one. They're like a ring spanner with a slot cut out, and can be incredibly useful for old rusted up joints. Having said that, I don't have one....

[Packedup]

Oh, and copper washers - They're used in some parts of the system, though not the bit you're fixing at the moment as far as I can remember (that's just a flare on the pipe causing the seal).

Another thing - When doing the unions up, they don't have to be hellishly tight - You will probably feel when the flared end is pressed into the hole firmly, and then tighten a little more. Once bled, press the pedal very firmly and feel for "creep", and check for signs of leaks. Repeat until you're happy it's all good, then take a steady test drive and double check it's all good.

[bmcecosse]

You said COPPER pipe - and copper should NOT be used for brake pipes - because it just is not strong enough, as you have discovered the hard way. It also 'age hardens' and becomes brittle - if the rest of your pipes are like this then get them replaced asap. Either use steel 'bundy' tubing - or far better Kunifer - which doesn't rot or harden. The pipe ends are 3/8" unf thread on the front cylinders - and you need to be sure the pipe goes into the cylinder dead straight - so you can get the end to screw on without cross-threading. The old end should come out using a ring spanner - but you were fitting a new cylinder anyway - and your new pipes will have nice new ends on them anyway. I NEVER clamp flexi brake pipes- no matter what you use it risks damaging them - could fail sometime later with very little warning.
The brakes are a safety critical item - for you and others on the road around you - the work must be done correctly and to a very high standard. You were talking about jamming the pipe back in !!!

[alex_holden]

Both ESM and Bull Motif describe the brake pipes they sell as copper. Perhaps they're actually made from a copper alloy like Kunifer.

[bmcecosse]

Hopefully!! But i would ask.

[Packedup]

The copper coloured pipes I've bought in the past have held up fine, from non-servo'd Minis with drums all round through to heavily servo'd repmobiles. Whether or not it is actual copper, or a copper alloy I don't know, and to be honmest I'm not going to spend a great deal of time caring about it either! Pretty much every specialist for the cars I'm into lists pipe kits as copper, and I'd expect there to be a lot of fuss over that if it is a problem.

As for clamping pipes, I'm no fan but did buy a hose clamp which comes in handy fault finding. To reduce/ stop leakages I'd put a bit of clingfilm or offcut of plastic bag under the filler cap, but I guess that's a bit tricker on a Minor than most cars

Of course, in this instance putting a bleed nipple in the cylinder connected to the main pipework would be a good method, thinking about it...

[Relfy]

OK, I've got a new pipe (copper-nickle for bmcecosse's interest) and reattached everything. Checked for it fouling the suspension and its all fine. Then I thought I would check for leaks, so pressed brake pedal, and this is where everyone can laugh, as I blew the top partially off the new cylinder! It pinged back and reassembled itself fine... but is it ok to use now?

*sigh*

[alex_holden]

Don't forget to bleed the air out.

Kunifer is apparently 90% copper, 10% nickel, so that's probably what you've got.

[Relfy]

*sigh*

So is that an affirmative - the cylinder should still be ok? I'm getting a bit stressed as I was meant to be in Coventry by yesterday.
Yeah. I need to bleed it all now, on my own, should be interesting. But I might just cry instead as thats what women are allowed to do. Actually I recommend it - makes you feel a whole lot better and then you can get on with the job!

Looking at the name - my quess would be kunifer is copper, nickel and iron: periodic symbols Cu, Ni and Fe. Dunno if thats true? What would the iron add to the characteristic of it?

[Relfy]

OK, that's it brakes bled and adjusted, wheels on.
I'll let you know how it goes...



Thanks for all the help!

[alex_holden]

It ought to be OK as long as you didn't get any grit in it when you put the piston back in.

I had to modify my master cylinder filler cap to make it fit my Eezibleed - hence why I've been trying (and so far failing) to obtain another cap. I'd recommend press-ganging a friendly neighbour into pushing the pedal for you while you operate the bleed nipple.

I think you're right about the Kunifer. Some googling seems to suggest the "Kunifer 10" alloy comprises roughly 87% copper, 10% nickel, 1.5% iron, 1% manganese, and small amounts of carbon, cobalt, phosphorus, lead, sulphur, tin, and zinc. There's also a "Kunifer 30" that is mostly 70/30 copper-nickel.

[Relfy]

I think you're right about the Kunifer. Some googling seems to suggest the "Kunifer 10" alloy comprises roughly 87% copper, 10% nickel, 1.5% iron, 1% manganese, and small amounts of carbon, cobalt, phosphorus, lead, sulphur, tin, and zinc. There's also a "Kunifer 30" that is mostly 70/30 copper-nickel.

Gosh. It ought to be called "Kunifeccomngsnpsplumbumzn" then. Might be a bit of a mouthful though.

[Packedup]

The cylinder should be fine, and in future do the leak checks after bleeding and with the shoes and drums back on!

I've used those little one way valve in a bit of pipe things to bleed my brakes, and never had any problems. Cheap ones are simply a nail stuck in a bit of rubber tube with a small split in it, more expensive ones have a valve and sometimes even a plastic bottle.