Hi,

My car is a 1984 Trans Am with rear disc brakes.
I have following problem with the brakes.

I replaced all 4 hoses. I replaced the piston seals
and dust boots in all 4 calipers. Then we bleeded the
system with the usual method. Pumping and loosening the
bleeder valve and so on.

The pedal is still soft. We spent hours! doing the bleeding.
The mechanics had the idea that maybe the seals stick to
the pistons and if we release the pedal they pull them back.
I pushed out the pistons and pushed them back so that I could
mount the calipers not more. It does not help, the pedal is
still soft.

I can drive with the car, let's say the brake is 70% or so.
But it is not enough, not so good like before and the pedal
is still soft.

Do anybody have an idea what can be the problem?
What are the typical mistakes that people can do?
Or are there any typical problems releated to brakes
and bleedeing in case of such a Firebird? Currently we do
not have any other idea and also mechanics can not advise
me anything. Is this a bleeding problem or something else?
What could I test in order to find out the problem?

Thank you,

Laszlo

 

Try bench bleeding your master cylinder, and then re-bleeding the system. Or your master cylinder could just need replaced.

 

Hi,

Please explain me what is a bench bleeding and how it is done.
Can I just bleed it by pumping and loosening the 2 brake lines?
Is this what you mean? I do not know exaclty how a master
brake cylinder should be bleeded.

Thank you very much,

Laszlo