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Just found out that my master cylinder is leaking into the servo. Could not see any obvious leaks round the rear brake cylinder or in the other usual places. Still the brake fluid dissapears. Hans guessed it was leaking into the servo, and that explains it. So, I need to restore the master cylinder. As Hans pointed out, there seems to be a lot of different models around. Does anyone have a list of sparepart numbers so I can start searching? I am going to Beaulieu Autojumble in September and normally you can find lots of repair kits there. In the mean time I will keep it on the road carrying a can of spare fluid. Thanks.

and that was a brand new one around 7 or 8 years ago. I paid about £130 for it.

Luckily we have ebay these days, here's three new ones on there http://www.ebay.co.uk/itm/Metro-brake-m ... 3369a7ed22

Thanks Stuart, I never think about E-bay. I guess I am very oldfashioned I´ll give that a try.

Now would this fit my car? No problem with different bores etc?

minisweden wrote:Now would this fit my car? No problem with different bores etc?

I think it would fit, I'm not 100% sure though.

Some Metros had the pressure reducing valve on the side of the master-cylinder, and others like yours originally on the n/s brake hose fitting, so I'm not sure if the outlet on the master-cylinder is different between the two types, I doubt they're any different myself.

minisweden wrote:Just found out that my master cylinder is leaking into the servo. Could not see any obvious leaks round the rear brake cylinder or in the other usual places. Still the brake fluid dissapears. Hans guessed it was leaking into the servo, and that explains it. So, I need to restore the master cylinder. As Hans pointed out, there seems to be a lot of different models around. Does anyone have a list of sparepart numbers so I can start searching? I am going to Beaulieu Autojumble in September and normally you can find lots of repair kits there. In the mean time I will keep it on the road carrying a can of spare fluid. Thanks.

If you give Biggred a call with a description of your cylinder they should be able to sort you a repair kit out.

There should be an indication on the master cylinder. Mine says AP, but I always forget if that's Lucas, Girling or Lockheed! That's why I bought the wrong kit. But it may be wise to strip it first to see if the bore of the m/c is not corroded and has no scratches. Else you are better of buying a new one. Mine was fine, so I just cleaned it and installed it again including the pistons with the old seals.
Only in my eager to refurbish it, I cut a plastic ring of the brake pressure reducing valve (there was some corrosion under it). But then after installation it kept on losing small quantities of brake fluid. Now I have removed the assembly again and it turns out there is a tiny hole in the groove where normally that plastic strip sits. So if you want to clean and paint everything, leave that strip in place! I have no idea what it does (I asked the Metro forum but did not get a response), so I filled it with silicone kit and placed a rubber band around it.

Stuart wrote:and that was a brand new one around 7 or 8 years ago. I paid about £130 for it.

Luckily we have ebay these days, here's three new ones on there http://www.ebay.co.uk/itm/Metro-brake-m ... 3369a7ed22

Thanks for the link Stuart, I've just bought one. Mine is leaking at the two rubber seals where the reservoir plugs into the cylinder.

For reference, I made an offer of £21, and that was declined, but with a note saying "on a single item purchase, £34.25 including postage is the cheapest I can sell this item for", so I made my second offer £24.26, which was accepted in under a minute.
I remember buying a new brake master cylinder from a motor factor for my Bronze for about £35, way back in the 1980s, so can't complain.

Of course, if someone knows where I can source just those two rubber seals, I'd be happy to hear.

faceofdoh wrote:Of course, if someone knows where I can source just those two rubber seals, I'd be happy to hear.

It looks like these are part of several repair kits I saw on Ebay. Even some have the split pin included (that usually corrodes away).

Hans Efde wrote:

faceofdoh wrote:Of course, if someone knows where I can source just those two rubber seals, I'd be happy to hear.

It looks like these are part of several repair kits I saw on Ebay. Even some have the split pin included (that usually corrodes away).

Thank you Hans, I've just done a search for those repair kits on ebay and found five hits. All seem to be different, and 3 were for non-servo applications. I'll have to work out just exactly which one mine is, now...