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MG MGB Technical - clutch master cylinder problem

My master cylinder was leaking last season so I got a rebuild kit. I removed the MC and replaced the first internal seal. The deepest parts of the cylinder did not come out. How so I extricate those pieces. My Haynes manual is now in the care of someone who didn't return it - I suppose this direction is given there.

Anyway I reinstalled the half rebuilt MC (a mistake I'm sure) and got everything back together topped up the fluid resevoir and began to pump up the line. Nothing is happening - do I have a major airlock? I opened the bleeder on the slave and nothing runs through - pumping the pedal or not. I can pump the pedal for ever and the resistance doesn't get any tighter.

Should I be adding/injecting the fluid from the slave in reverse up to the MC? This would remove all the air. BTW the hardest thing I have ever done while doing the work on my 69B was to get the lower bolt and nut on the MC back together.

Thanks for your help.
C. Spenceley

I think you need to remove the cylinder and finish the rebuild job. The old rubber cup usually binds/sticks. Tapping the end of the cylinder on a wood block will usually get it out. If that doesn't work and you have an air compressor you can get it out with an air nozzle inserted into the cylinder banjo, don't use high pressure and tie a rag around the end of the cylinder to keed parts from flying away. After all the parts are out, clean and inspect the cylinder bore for pitting and wear. If it isn't smooth it should be honed or replaced. Rebuild the complete cylinder and try it again.

Clifton Gordon

I removed the master cylinder again this time I got it fully apart. Rplaced all seals and reinstalled MC. This time the job went about 3 times as fast as the first go around. The bleeding of the system still didn't go as expected. I pumped the cylinder about 500 times with no pressure increase on the pedal but the fluid did drop slightly in the reservoir. I operated the slave cylinder by hand and did feel some resistance there. I repeated pumping the MC then the slave and this brought up the resistance in the pedal. I tried bleeding the slave but still no air in or fluid out but my clutch is shifting as it should so I am happy.
Chris Spenceley

This thread was discussed between 31/05/2006 and 01/06/2006

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