Hi,

 

Have not posted here for ages, but I am now having a problem that I am struggeling to get to the bottom of. Had the Z'ed (1993 NA) for 12 years and so far managed to sort most things myself.

 

The issue is the 'feel' in the brake pedal after driving for a while (and also after leaving the car just to idle for 20 - 30 minutes). The pedal is nice and firm when it is cold, but when it get hot under the bonnet there is a spongy feel if you keep pressing the pedal for 30 - 60 seconds (feels OK to start with and it passed the Irish NCT - MOT eqvivalent without any problems as it is now). After pressing for a while the pedal start to slowly give, and will get closer to the floor. Have replaced the brake fluid, and I do not think that there is any air in the system (have bleed a few times).

 

I cannot see any leak anywhere and I am from what I can see not loosing any brake fluid (no need to top up - it is still plenty of fluid in container).

 

Could this be a problem with a Brake Master that is on its way out ? Any help, so that I can find the reason would be highly appreciated.

 

/ Hans

It sounds like you have either got a small air leak in the brake booster or maybe a leaking seal in the the brake master cylinder.

If this is a air leak in the brake booster, would it be likely an 'internal leak' (i.e. inside the booster) ?

 

Or would it be vacuum pipes that are more likely to be the cause ?

 

/ Hans

I got similar problem that i like to know. I have no brakes at all, i been reading in other forums and i think its could be my brake master cylinder with some air in. I think previews owner installed new bmc and didnt bleed out all air from the system. I will tru to fix tomorrow i let you know if its that.