brake master cylinder rebuild

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garyinwestoz
Posts: 390
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
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brake master cylinder rebuild

Post by garyinwestoz »

ImageIm rebuilding my brake master cylinder
have all the new rubber seals.

there are 4 of 1 kind and 1 of another ( similar different lip)

I didn't take notice of what seal went where when I took them off (- over 6 weeks ago)

can anyone tell me where this different seal goes?

my guess is the back end of the top drawing - as it looks a little different to the others (and is in reverse)

Image

haynes manual doesn't show clearly

Image

photo of different seal

Image

here is a few photos of what I have

Image

Image
Last edited by garyinwestoz on Mon Jul 02, 2018 7:53 pm, edited 2 times in total.
74 525 auto
76 525 - 4 speed, LPG and holley carb- restoring
77 528i- 4 speed manual
77 528i -4 speed manual getting rusty
79 528i auto - a SA car?
80 528i auto - ready to relicense
81 528i +3.5ltr - auto - restoring
86 525e 5 speed manual- dd
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Mike W.
Posts: 2782
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: brake master cylinder rebuild

Post by Mike W. »

I think you're right and that would make sense. Since it's a dual circuit M/C you want something separating the two hydraulically. That seal would do that. Your pics didn't come thru, except for the BMW fans one, they just take me to a Google longin screen.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
garyinwestoz
Posts: 390
Joined: Thu Jan 29, 2009 9:05 pm
Location: perth, australia
Contact:

Re: brake master cylinder rebuild

Post by garyinwestoz »

Mike W. wrote: Mon Jul 02, 2018 11:09 am I think you're right and that would make sense. Since it's a dual circuit M/C you want something separating the two hydraulically. That seal would do that.

Your pics didn't come thru, except for the BMW fans one, they just take me to a Google longin screen.
okidoki will give that a shot.

note:
It seems that google photos required the folder to be "shared"- so changed that- hopefully photos show up now

ps all these new seal parts cost me $64 from Perth Brake Parts http://www.perthbrakeparts.com.au
74 525 auto
76 525 - 4 speed, LPG and holley carb- restoring
77 528i- 4 speed manual
77 528i -4 speed manual getting rusty
79 528i auto - a SA car?
80 528i auto - ready to relicense
81 528i +3.5ltr - auto - restoring
86 525e 5 speed manual- dd
User avatar
Mike W.
Posts: 2782
Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Re: brake master cylinder rebuild

Post by Mike W. »

Pics do work now! And kudos to you for actually rebuilding it and not just replacing it. Not difficult but it's becoming a lost art.
Mike W.



1980 528i, 3.5 euro, 5 speed conversion
1981 528i, 3.6, Recaros and more. Project
1998 328is, quick and efficient, but not satisfying
2000 528iit, Vacation mobile/wife's grocery getter
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