44 replies to this topic

[b_sdaddy]

Dear all,

 

HELP! Brake experts required!

 

 

my brake cylinder needs replacing.

 

As part of my on-going dilemma, I am trying to get my brakes MOT friendly:

 

Already replaced shoes, wheel cylinders and hoses.

 

Now, as a domino effect, the master cylinder is not working, but looking on MiniSpares, it's not as simple working out which one I need:

 

yellow, green black band? metric UNF? LHD RHD....?

 

 

 

my mini is a 1978 Mk4 LHD.

 

 

The current master brake cylinder has plastic reservoir with connectors on screw lid.

 

Is it a case of visually looking at the existing unit and matching it to the photo on MS website.?

 

I 'think' GMC171 looks like it.?

 

 

 

 

and to add misery to misery, the long copper pipe F to R also needs replacing!  I think HMV102 will suit (non-servo)

 

and last thing:

 

 

copper pipe from rear T-piece to N/S/R brake hose is leaking. Obviously damaged it when replacing rubber hose.

 

being LHD, do I mirror this part.? on the schematic, part 8 (HD25 N/S) is significantly longer than part 9 (HD6 O/S). Cant see which is which, but as the master cylinder is N/S on a LHD, surely I need part 9.?

 

 

 

any advice appreciated.

 

will if needs be, call minispares, but living in Belgium, it's not the cheapest of options!!

 

 

thanks all

[Spider]

Maybe post up a photo of yours so we can all be sure of what you currently have.

[b_sdaddy]

OK

 

will do...

[tiger99]

Please do not use copper brake pipe, ever. It has very poor fatigue properties and is dangerous. It is very important to be sure that you are getting Kunifer, also called cupro-nickel, which is manufactured and properly specified for brake systems, which copper is not. It is also probably illegal in Belgium, as it is in various parts of Europe, the USA and Australia, to use copper. Sadly UK law is out of step with reality and we still allow this dangerous stuff here.

 

Kunifer tube will be supplied to comply with ISO 4038 and SAE J1047, but there is no such specification for copper brake pipe.

[b_sdaddy]

Dear Tiger99,

 

so all the thousands of 'oldtimers' (classic cars & minis) here in Belgium with their original, copper braking systems are illegal.? Surely not.? You can't expect me and the rest of us, to rip-out all the copper brake pipes in my mini when it's been working perfectly well for 40 years..As fatigue goes, that's not bad!

 

Do you have a link or information available for a complete Mk4 mini braking pipe set (LHD), made from cupro-nickel.? I'd be interested in the price point, compared to the £90 from mini-spares (copper set)..

 

 

cheers

[spraybeater]

Dear Tiger99,

 

so all the thousands of 'oldtimers' (classic cars & minis) here in Belgium with their original, copper braking systems are illegal.? Surely not.? You can't expect me and the rest of us, to rip-out all the copper brake pipes in my mini when it's been working perfectly well for 40 years..As fatigue goes, that's not bad!

 

Do you have a link or information available for a complete Mk4 mini braking pipe set (LHD), made from cupro-nickel.? I'd be interested in the price point, compared to the £90 from mini-spares (copper set)..

 

 

cheers

Just bought some cupronickel  from DSN classics ! always used to make them up myself  in steel/copper& cupronickel but since retiring don't have

access to equipment now ,and proper flaring tools are expensive. My personal view is these are well made and labeled and a good price   

[tiger99]

Cupronickel is almost the same price as copper, and very easily available. There is no reason not to use it. And if copper has been in use for 40 years, and you don't know how many pressure cycles it has seen, and to what peak pressure, how do you know how much of its fatigue life remains? 40 year old copper is potentially lethal, and I would indeed suggest that it be ripped out and replaced.

[b_sdaddy]

So when I go to minispares and order a new brake pipe set, I only see this:

 

http://www.minispare...px|Back to shop

 

I don't think they are aware of the dangers from still using copper for braking systems...

 

 

Where in the UK can I get the same set, but in cupronickel.?

 

cheers

[b_sdaddy]

 

Dear Tiger99,

 

so all the thousands of 'oldtimers' (classic cars & minis) here in Belgium with their original, copper braking systems are illegal.? Surely not.? You can't expect me and the rest of us, to rip-out all the copper brake pipes in my mini when it's been working perfectly well for 40 years..As fatigue goes, that's not bad!

 

Do you have a link or information available for a complete Mk4 mini braking pipe set (LHD), made from cupro-nickel.? I'd be interested in the price point, compared to the £90 from mini-spares (copper set)..

 

 

cheers

Just bought some cupronickel  from DSN classics ! always used to make them up myself  in steel/copper& cupronickel but since retiring don't have

access to equipment now ,and proper flaring tools are expensive. My personal view is these are well made and labeled and a good price   

 

just googled DSN, et voila! just what I need; a complete set of brake lines in copper/nickel. AND they do the master cylinder and hoses as well! Cheers for this.

[Blatherskite]

Cupronickel is almost the same price as copper, and very easily available. There is no reason not to use it. And if copper has been in use for 40 years, and you don't know how many pressure cycles it has seen, and to what peak pressure, how do you know how much of its fatigue life remains? 40 year old copper is potentially lethal, and I would indeed suggest that it be ripped out and replaced.

Intetesting point when EU regulations require you to fit parts made to original spec...

[b_sdaddy]

How important would it be to change the pressure valve and rear wheel cylinders at the same time.?

 

I've 'budgeted' for a brake pipe set and new master cylinder, and they've come back saying that I'll also need pressure valve and rear wheel cylinders..

 

budget now doubled to £300!

 

IF it is indeed 'important' to do so, or due to metric/imperial etc. impossible without the new pieces then needs must, but if just advised, then can it done without these being renewed.?

 

 

cheers as always

[Spider]

How important would it be to change the pressure valve and rear wheel cylinders at the same time.?

 

 

What condition are the ones you have in?

Apologies here, but I seem to recall (???) that you recently replaced some wheel cylinders???

[b_sdaddy]

Yes, well remembered. I have replaced leaking front wheel cylinders. And Shoes (still drums to front).

 

Replaced rear shoes & rear brake hoses also.

 

Now there's a leak in master brake cylinder, and one of the copper pipes front to rear needs renewal.

 

Original brake cylinder no longer available, so only one available is GMC227.

 

I have a diagonal split system fitted now, and I have been told by DSN Classics, this is effectively going to be a front-rear split system.

 

I have no receipts from previous owner to say this (pressure valve), has been replaced, so must assume 40 years old (50,000 miles).

 

Minispares happy to supply pipe set & master cylinder only, and have not recommended anything else.

 

DSN classics who were suggested as they use copnickel, have given a more extensive list inc. rear wheel cylinders & pressure valve.

 

 

Aware that on minis, don't replace unless it's broken, as it usually opens a can of worms.....

 

The money in the long term will be forgotten, and really, I don't want to be touching these brakes again for a long time, so want to get it right. Just don't want to spend money if I don't need too.

 

 

cheers all

[Spider]

Ah, OK, so sounds like you need a GMC167 MC?

 

Available here:-

 

http://www.somerford...roducts_id=3503

 

I just bought a few last week.

 

It also appears that your particular model never have a Pressure Shut Off Valve or the like.

[Mini Mad Drakeley]

first question should be in my mind, what system do you have?

in 1978 they fitted a terrible system as the pressure regulators ran out and everyone was on strike or something so they basically bodged it by running individual pipes to the rear wheel cylinders through 2 t-pieces on the bulkhead and used 1/2 inch bore rear wheel cylinders.

 

its an absolute nightmare as the rear cylinders have a tendency to seize up and its a miracle if you can bleed it properly, my mini is having the whole system stripped out at the moment