Brake problem again!!!!

facade wrote: You might find that the fault lies with the servo, rather than the master cylinder.
If the pedal stays up and solid without vacuum in the servo, but gradually sinks when the engine is running, the fluid level isnt going down, the flexible pipes are ok and it has had a new master cylinder, it is about the only thing left.

You could be right but when I was taking off the old cylinder I had to prize it off due to the vacum. It was pretty solid, so I guess it must be working?

Hi,

I'm having a problem with my breaks too, started squeeking last night when breaking but performing ok, today the noise has stopped but I nearly went into the back of someone at a roundabout as the car didnt stop, its usually very sharp at stopping. Fluid is ok, no leaks or visual damage, I can put the peddle to the floor and it feels very hard and slow and doesnt stop the car very well, I dont even think an emergency stop is possible, I tried it, just felt like pushing something very heavy with my foot, not the usual feeling where I tap it and everything in the car flies forward because they usually work so well. I had to leave double the space between cars in front due to it, there is no ice or snow on the roads I use. Its cold here no different to last few days though and its only done 700 miles. Any idea what it could be?

Kier wrote: Hi,

I'm having a problem with my breaks too, started squeeking last night when breaking but performing ok, today the noise has stopped but I nearly went into the back of someone at a roundabout as the car didnt stop, its usually very sharp at stopping. Fluid is ok, no leaks or visual damage, I can put the peddle to the floor and it feels very hard and slow and doesnt stop the car very well, I dont even think an emergency stop is possible, I tried it, just felt like pushing something very heavy with my foot, not the usual feeling where I tap it and everything in the car flies forward because they usually work so well. I had to leave double the space between cars in front due to it, there is no ice or snow on the roads I use. Its cold here no different to last few days though and its only done 700 miles. Any idea what it could be?

If its very heavy and stiff, and the car struggles to stop then its likely the servo has gone. Its not holding a vacum to help assist the pedal.

You may find that the vacuum pipe to the servo from the manifold has split, or the non-return valve at the servo (the spigot that the rubber pipe goes to, that fits into a grommet on the servo body) has blocked up.

Engine off, press the brake a few times. It should go shhhh shhhh shhhh shhhh shhh shh sh s. as you use up the vacuum stored in the servo chamber.

Hold the pedal down and start the engine. The pedal should sink down.


If it is a diesel jimny, likely the alternator belt is broken. (the alternator should drive the vacuum pump)

Ok I am going to replace my flexi-hoses Saturday because the problem has got worse and the pedal is going further down (only occasionally).

Just wondered if the other posters who have had the same issue have since found the problem?

lv'e been reading about the problem your having with your brakes and it sound a bit like the problem GROMMET had on his on this red jimny when he fit a 3" lift with longer brake lines ,he was not bleeding the bleeder on the load sensing valve which the rear brake pipe is fitted too so air was still in the brake lines.