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MG MGB Technical - brake problem, 74 bgt with servo


after a few weeks from selling my bgt, i realised my mistake and bought another one! its a 1974 bgt in purple, nice bodywork but unused for 9 years. it has a full mot, but is in need of attention before i can use it reguarly!

my main worry is the brakes, on first application they are fine but a second or 2 on the pedal and the pedal drops and can even go to the floor! as you can imagine, i dont want to drive it at the minute because of the problem, but on the other hand, i want to be out in my car!

Any ideas?

also it misfires from low revs and has no power below 2k revs, but drives perfect above that.

another problem is the oil pressure does not move above 20, even when revving from cold, this cant be right?

John Collins

Sounds like the seals in the brake master cylinder are leaking internally. Pull all four wheels and inspect the brakes, making sure the seals in the calipers and wheel cylinders are not leaking.

Install an auxiliary oil pressure gauge to make sure that the oil pressure is truly not that low. If the oil pressure is that low, you are looking at possibly needing new engine bearings and maybe an oil pump.

Have you done a tune-up? Checked the engine compression? Set the valve lash? What do the spark plugs look like? Misfiring can be caused by the plugs fouling, worn ignition parts, vacuum leaks.


This thread was discussed on 08/01/2008

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