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MG MGB Technical - Brake Master cylinder rebuild

Hi Guys
As title says, about to recieve new re-furb seal kit for M/C on dual circuit 77 BGT (MGOC).
However, the small spring and shuttle will not come out ( Not the twin spring & shuttle for the main workings of the cylinder, the small one operating the sensor). The wonderful Mr Twist says " wear a glove and tap it hard".
It will not budge. Even tried hooking a spring under the spring retaining collar, it will not budge, even though I can depress the spring.
I'm also missing the small stepped pin on the main (inner) shuttle, Screw ( stepped phillips head) holding down the reservior ( had to drill it out !) and the metal outer collar that holds the large seal cap on pushrod/M/C body.No one seems to sell them !

Can anyone help or offer advice ?.
I'm afraid finances don't run to a new M/C and I'd like to keep as much O/E as possible.

My trials and tribulations of the rebuild over the years are available at >
P Liles

Have you unscrewed the switch?
PaulH Solihull

I had the same problem but unfortunately it was completely welded in with rust, if you can't get it to move through the switch hole, (unscrew the switch and CAREFULLY try and move it with a screwdriver or soft metal rod), then you will probably need a new master cylinder, I think a brand new one was about
Pat Gregory

I remember having that problem too. If my memory of getting it out is correct (I may have it mixed up with another job) I got it to move by driving it just a little deeper into the bore with a punch. Then I was able to bring it back by accessing it through the switch hole. A little at a time I was able to move it back and forth enough that I was able to remove it. Don't spare the penetrating oil.

C R Huff

This thread was discussed on 09/05/2012

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