Brake master Cylinder fault?

[Chris Z]

Hi everyone, my brake master Cylinder I believe has gone, ive got brake fluid in the foot well... and no brakes, the pedal goes to the floor. I've got a 1974 02 E6, I've had a look on the net and can't seem to find one that looks the same? I'm no expert and don't know what else may be compatible? Any help would be much appreciated. Cheers, p.s I'm in the UK. 

[02Les]

This came up a week or so ago from another guy in the UK. Maybe of some help. BTW, nice Touring.

 

https://www.bmw2002faq.com/forums/topic/225800-1602-brake-mst-cylinder/?tab=comments#comment-1275761

[Chris Z]

Thanks  for your response, Cheers Chris 

 

[dlacey]

Chris,

the pushrod seal has failed, you need to get the cylinder rebuilt. Replacing it is tough because this is an RHD-only part.

The rebuild kit is available, take care not to damage the cast iron part when removing the old piston...dont whack it too hard, use a grease gun to pump the pistons out if they are stuck.

dave

[Chris Z]

4 minutes ago, dlacey said:

Chris,

the pushrod seal has failed, you need to get the cylinder rebuilt. Replacing it is tough because this is an RHD-only part.

The rebuild kit is available, take care not to damage the cast iron part when removing the old piston...dont whack it too hard, use a grease gun to pump the pistons out if they are stuck.

dave

Ok, thanks Dave I think a repair kit is the answer then. Its something I can order off Ebay or auto doc I hope? Regards Chris 

[dlacey]

https://www.jaymic.com/brake-master-cylinder-repair-kit-rhd-bmw.html

 

you will likely need to hone the bore to make sure the surface is in good condition...you can do that with a piece of emery cloth wrapped around a wooden dowel mounted in an electric drill...there are proper tools, but that is adequate..

[dlacey]

https://shop.bmw-classic.de/bmw-classic/de_DE/original-bmw-teile/fahrwerk/34-bremsen/340817-hauptbremszylinder_of_c.kgmkqim58aaafpc6lg1nqb/page1.html

 

[Chris Z]

30 minutes ago, dlacey said:

https://www.jaymic.com/brake-master-cylinder-repair-kit-rhd-bmw.html

 

you will likely need to hone the bore to make sure the surface is in good condition...you can do that with a piece of emery cloth wrapped around a wooden dowel mounted in an electric drill...there are proper tools, but that is adequate..

Thanks very much, very helpful! Cheers Chris 

28 minutes ago, dlacey said:

https://shop.bmw-classic.de/bmw-classic/de_DE/original-bmw-teile/fahrwerk/34-bremsen/340817-hauptbremszylinder_of_c.kgmkqim58aaafpc6lg1nqb/page1.html

 

 

[Mike Self]

6 hours ago, dlacey said:

you will likely need to hone the bore to make sure the surface is in good condition...you can do that with a piece of emery cloth wrapped around a wooden dowel mounted in an electric drill...

A brake hone is an inexpensive tool and well worth the price, as you can use it for all your brake hydraulic overhauls.  I'm still using the one I bought in 1967 to overhaul the brakes in my Renault, well before I bought my '02.  A proper hone will insure you get an even and round finished bore.  And if it turns out that the pits can't be honed out, I'm sure there's a place in the UK that can bore out and sleeve your M/C.  There are shops here in the US that do that for hydraulic cylinders fitted to vintage cars that are NLA--usually in brass or stainless steel.

 

mike 

 

 

[Chris Z]

Ok, thanks Mike. I've ordered the repair kit as advised by dlacey. I'll order up a brake phone too. Much appreciated, cheers Chris