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MG Midget and Sprite Technical - Replacement / Pattern Brake Master Cylinder?

Morning all,
And... todays leak is... the brake master cylinder, or so I think. After sorting fuel leaks, hoping I've sorted an oil leak (front rocker cover nut not tight), I've now noticed a small pool of fluid on the drivers floor mat, directly under the brake pedal, with fluid also noticeable on the pedal itself. I removed the pedal box cover, and noticed fluid around the seal and shaft of the M/C.
So, has anybody bought a replacement M/C from Moss recently? They're 60 and should sort my problem, but... what's the quality like? Are they comparable quality to OEM, or are they like a lot of other pattern motor parts that come out of China?
The alternative is I buy the seal kit and either have a go at rebuilding it myself or get a specialist to do it for me. Would this be the better option, to salvage the original Lockheed one (though does look pretty manky), perhaps stripping and repainting the body/casing at the same time, or just go with new pattern part? It is a single line system, so even though I've never attempted anything like this before, I guess it makes it a little more viable than the later dual line jobbies. Thanks
M Weller

i bought the Moss M/C replacement a good few years ago and found no problem with it. And yes it is a straight forward task to replace and then bleed. For me the convenience of knowing that it was a likely bolt on solution out weighed the task of rebuilding the original. . . I believe I still have the Lockheed one somewhere as a reserve.
P Bentley

many might vote for a seal kit and could well be correct but if you wonder about the quality of master cylinders what about the quality of seal kits?

Then you need to carefully check the condition of your existing mc to check it's worth fitting a new seal kit to because if it leaks after fitting the new seal kit do you blame the kit or the mc.

Lots of info in the Archives and replies here and now can update quality concerns, if any.

As you can guess I'm more for replacing the mc and with a clear one then you can see at a glance the level and condition of the brake fluid every time you lift the bonnet (brakes should be the first thing you think of when lifting the bonnet anyway). Good opportunity to fully flush the brakes and change the brake fluid too.

I last had the (clear) clutch mc changed nearly three years ago and it's been fine, the (clear) brake mc was on the car when I got it nearly 10 years ago and has been fine.

Moss are not the only suppliers around too.
Nigel Atkins

If you don't want to use Moss then Powertrack are a useful supplier of decent quality stuff.
Bob Beaumont

I have always fitted seal kits, as long as the cylinder bore is in good condition.

However, Nigel makes a very good point about the possible quality of seal kits that are now available.

In the past, I've always used genuine Lockheed kits, or Unipart kits - which were probably Lockheed, as likely as not.
Dave O'Neill 2

Just checking Mike.
My leak was a pipe from the reservoir (big clear plastic type pot on a separate stand) to the MC. It covered everything in fluid like yours has but a replacement pipe fixed it.
Dave Squire

Thanks for your thoughts guys. I'd like to have a go at doing this myself with a seal kit, but two things concern me. One, its the brakes... if I make a hash of fitting, say, a new carpet set, it's no biggie, but brakes... And two, even if I manage to do it properly, being the first time I would have attempted anything like this (I haven't even changed brake fluid/bled a system before), I can foresee my borderline OCD side turning it into a 3 day job, or more. And if I'm honest, I'd rather be out driving the thing.

Re genuine lockheed seal kits, is it just a case of walking into your local factors and giving them the chassis? Or are they only available from marque specialists online?

And are the new Moss M/C's the clear type or are they metal, like the OEM? Not clear from the catalogue.

I'll check out Powertrack as well. Thanks
M Weller

Dave, not sure what you mean there, I'll pop out and check... Mine is a late 1275 single line system. Is your car the same model?
M Weller

Dave has a 1500 which has (IRCC and from the description) a separate tank to the master cylinder joined together by a pipe/hose.

Brake fluid will attack your paintwork if split so plenty of damp rags and a full watering can are best kept handy for spills or leaks.

I totally agree about the ratio of fixing to driving but brakes are THE most important thing on the car so need sorting, if it takes three days so what, pick three wet and cold days (some coming up soon if the forecasts are right).

I've got to change the brake fluid on mine and I'll be doing it the very slow gravity way, I've seen and had others bleed the brakes fast by pumping and then had to redo it later as there's still air in the system, professional and racers had do things quick, we don't.

For most work on my car now I look for three days in a row when I can do the work, such as an upcoming rad change, to allow for my mood (I ONLY enjoy driving my midget), things going wrong and the need to possibly get unexpected parts when the shops are open. If I get it done sooner great, if it takes longer so be it.
Nigel Atkins

The original Lockheed repairs kits are probably not available from your local factor given the age of the car. Its very likely to be a pattern part which may have quality issues as Nigel intimates. The marque specialists are likely to offer pattern parts. Personally I try and purchase new old stock as there is more certainty it will be ok. Powertrack and the like buy up NOS so may be able to supply (Although can be a bit more expensive)
Is yours the can type? if so its probably quite old and a new replacement may be a safer bet rather than just new seals. Its also a straight swap so you won't get bogged down worrying about if the seals are correctly fitted!
Bob Beaumont

I rebuilt several and nver could figure out why the seals always turned to bubble gum... i was told the orginal seals were made feom natral rubber and not compatiable with patrolium based fluid.

There not easy to rebuild, if i were to do it today id ship it off to a pro to rebuild that specialises in rebuilding old masters and slaves

If i bought new make sure you have a good warrenty that they will honor for at least a year, cus these things are NOT cheap... and i doulbt these from moss are actually orginal new equipment from the factory, but are really just rebuilt as sort of new-ish like...thus the need for your core... so they can continue to build like sort of new-ish for the next guy


Personally I'd pay under 60 for a new clear plastic mc for the reasons I put earlier, easy to see level and colour of brake fluid with a quick glance, plus I'd take the opportunity to fit a set of Goodridge hoses (27) if not already fitted.

I've never understood how owners are prepared to pay silly money on cosmetics and bling yet baulk at investing lesser amounts in decent brakes and tyres and vital parts and components.

But I can see that if for a few pounds you can successfully repair what's already there it's a viable option.

Nigel Atkins

"There not easy to rebuild"

That depends on which cylinder you have

North American cars had dual circuit master cylinders fitted from 1968. These are trickier than the UK-spec single circuit cylinders.
Dave O'Neill 2

Thanks for that dave

I wanted to suggest that but wasnt sure on the details
1 Paper

Nigel, cost in this case i.e. brakes that work, has never been a consideration, for others possibly, but not for me. All I'm looking for is the best option, from a functionality POV. I don't want to spend 60 quid on some junk + fitting costs if I can pay a similar amount for a professional to rebuild what 'might' be a better quality unit to start with.

All I'm looking to do here is pick the collective brains of people far more experienced in this area than I am, and proceed accordingly.
M Weller

I wasn't suggesting you were one of those that prefers bling to good brakes, etc., it was a general comment, I don't think anyone on here fits that pattern.

And I agree with you if the mc you've got is better quality and still in good condition and it can be reconditioned with good quality parts then it's worth doing (but I'd still go with the new clear plastic as long as the quality hasn't dropped from ten and three years ago).

I put 27 for the Goodridge brake set, that was wrong, it shows as 44.95 on MGOC Spares for the set, I'd certainly have those over risking current or worn rubber ones.
Nigel Atkins

Yes, i think it makes sense to do the braided hoses at the same time. I'm also thinking of changing the organ style throttle pedal for a pendant type, as the current hinge / linkage is rather tired.
M Weller

This thread was discussed between 21/04/2017 and 22/04/2017

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