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MG MGB Technical - brake leak

Yesterday I checked the level of the brake fluid and found that it was extremely low. At the same time I noticed a large puddle of an oily substance on the floor mat on the drivers (left) side. Am I safe to assume this oily substance is brake fluid? If so where would it be leaking so that it would get on the floor mat inside the drivers compartment. The car is a 1974 B (chrome bumper) and had not been driven for aprox 2 months.

Any help would be appreciated

Mine was a clutch but its probably the same- seals in the master have gone and it travels along the shaft, down the pedal and drips on the floor. Suggest a new cylinder, rather than replacing the seals. As the cylinder is usually corroded HTH m
Michael Beswick

Rick, The brake master cylinder is leaking past the seals out through the dust cap and dripping onto the carpets. Fit a new master cyl as its hardly worth fitting new seals which will probably leak again in a fairly short time.
Iain MacKintosh

I second Iain's advice.

I overhauled my leaking brake cylinder. It was fine for a while but started leaking again after less than a year, so replaced the whole cylinder and have had no problems so far.

In case you don't know (as I didn't!) you can get to the back of the cylinder from the driver's footwell by removing the rubber bung in the bulk head.
D Lewis

Rick, If you are using DOT 4 or DOT 3 brake fluid you need to remove the pedal box and clean everything where the fluid leaked. If not cleaned and repainted your old paint will come off and the area will rust. I tried replacing seals in my brake master cylinder several years ago and the leak returned in about six months. The master brake cylinder in the 74 isn't easy to rebuild.

Clifton Gordon

This thread was discussed between 13/03/2006 and 18/03/2006

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