Brakes: Needing help

[Jase EK]

hey there

ok.. short story is.. upgraded rear to disc, and the front to ek9. this was on a ek1 with drums on rears. when purchased all the setup, i was told from seller, i can use my stock MC, booster, prop valve :S
i was little confused, coz i thought u gotta upgrade the complete setup. However was convinced that you can use the stock one for now and upgrade later.. so there for i went ahead and installed it all correctly.. and then time to bled the brakes.. RL, RR, FL, FR, .. mate in car, few pumps, hold pressure, undo nipple, let bubbles out.. etc etc..

This is where I am having trouble. i kept doin it until there was no air in the lines and the brake pedal felt hard in 1 or 2 pumps. while doin it i did always checked fluid in resevoir, So I thought I was done and started the car and thats when the brake pedal immediately became extremely soft and I could push the pedal to the floor easily. If I quickly pumped the brake pedal while the car was running it would build up pressure but then immediately go almost to the floor. then i checked the big vacum line and it was all good.
i then did bleed procedure again with the car on, however this time.. pedal dont hold pressure, its always soft ..

so i gave up for the day.. and yeah.. any you guys have idea ?

[Zdster]

Pretty sure that is the master cylinder.

There is a big difference between the old and new setup that you have, so I am pretty sure that at a minimum you will need to upgrade the m.c. and then look at the p.v.

[Jase EK]

hhhm.. thanks.. i'l check up on the MC.. hard to swap ? any DIY ?

[Jase EK]

also.. when i did the brake swap.. the MC was drained to the max.. no fluid left.. im thinkin still air in the lines ?.. im gonna try bleed em again for a few more times and see how it is..

[EG5[KRT]]

you have to bleed the master cylinder first .. then once that is bled up properly you have to bleed the rear brakes then front etc...

thats wat u normally have to do if the MC is totally drained...

[Jase EK]

will do some searching..

[bOoStn]

Yeah, it sounds like a master cylinder. They rebuild them at certain major services (i cant remember if its 80k or 120k). If you want to bleed the master cylinder, remove it from the car, stick a screw driver in the back of it to push the piston(s), when you push in, let the fluid come out, then put your fingers over the holes where the fluid comes out, let the piston come back, and repeat. Just do that till the air is out of the master cylinder, then refit it to the car, and do another brake bleed. If you still have the same problem, you're most likely going to be up for a master cylinder rebuild