which one is failing?

[e21manic]

hey there guys,my DIY restoration on my toy E21 continues. now am currently getting the carbie overhauled and getting the brakes done. then bodywork the project compete!:top:i have a question about the brakes. when the car engine is off, the pedal travels straight to the floor. when the engine starts it travels to the floor too with the same effort as in its doesnt feel lighter.. pump it a few times and the same thing. when i took it for a drive the braking power was as good as useless as i had to actually use the handbrakes to come to a stop.. so i have read up on how to dismantle the brake master cylinder (MC) and all that but what got me thinking is wether this might be a problem with the brake booster? how would one differentiate which one is failing?further info.. there is no fluid leaks but there are small bubbles in the brake fluid resevoir. this car has not been moving much for a long time too. will be working from the brake pads up to the MC looking for faults but i would like to know what i might be facing here...will be taking the MC apart soon but only for learning purposes.. will be getting a new one and replacing it.. on that note would a set from an e30 fit? am planning to change the MC and the booster as well.. what do you think?am very noob and learning as i go along, so any info at all would be much appreciated...:listen:thanks a lot guys!! :wink:

 

[IsaacVky]

Maybe a bleeding of the brake fluid will do.
And leaking booster.

 

[pussy]

yes, the MC is failing... the e30 will be able to fit.. btw, u can use the e28 larger MC, but make sure it is the non hydraulic MC(two outlets)..versus the 3 outlets.. u need to use the 3 outlets..

 

[e21manic]

thanks for the relies and the input guys!!
really apreciate it.
pussy: the e28 unit would be able to fit in plug and play or would i need to do mods? the unit in my e21 is the 'long arm' type. its not on the firewall.
plus i read somewhere that if the MC fails and fluid gets into the booster then it would screw the booster up to.. is that true?
lastly, what would a unit from an e28 cost? inlcuding and without the booster pump?

thanks a lot guys!