Brake Pedal Going To Floor

[TKR]

I recently did a brake upgrade on my gts r32 to gtst calipers on front... brakes were oki before hand and freashly bleed.

I fitted new disc's pads front and rear. *no leaks of fluid or air getting into the calipers*

( i have converted my rb25de to a rb20det if that somehow can be a issue)

I re bleed the brakes twice properly and the pedal still sinks to floor and i have to pump it up to get them stiff and soon u move or start engine it sinks again ..

thinking maybe a vacum leak but not to sure ;/ everything is in the right spot and that .. kinda shitting me ... or maybe booster.

any advise will be good or anyone had this issue . thanks alot

andiii

[Lupes]

How did you push the pistons back in the calipers?

You should always open the bleed nipple and clamp the brake line when pushing the pistons back. This way fluid from inside the caliper comes out of the bleed nipple and doesn't go back through the lines, as having fluid being pushed back into the master can ruin seals inside it.

Sounds like the master could be gone.

Edited February 26, 2009 by Lupes

[TKR]

hmm now to think of it i just pushed them back normaly with a pry bar XD

ill pull it apart this weekend and check.

thanks lupes

Edited February 26, 2009 by TKR

[Lupes]

No worries. That's what we do at work whenever we do new pads.

Might not be the problem but definitely possible if you did it with a pry bar hehe.

[TKR]

well i work on euro cars all day;/ and new ones so its always never been a problem but i never fort about that .. old fluid been pushed back up the to seals -.- 12+ years old good bye seal

[Mike__]

Sounds like you did exactly what i encounted.

My master cylinder carked it when i was changing/flushing fluid, pads, discs. pumped the pedal too far down beyond the point of where the rubbers have been making continous contact during normal braking & destroyed them

Bought a recon unit and good as new Think i paid ~$200ish

Mike

[blind_elk]

Calipers are on the right way (bleed nipple on top)? I know it's a stupid question, but ...

You replaced the master cylinder? In my 240Z, I did the same, there was a little rubber block inside the booster. It sits between the master pushrod and the booster pushrod. It dropped into the booster. Had good pedal pressure, until vacuum was applied to the booster, ie start engine.

[TKR]

mike--- haha yeah i think i blown the seals.. haha lucky had a spare on my half cut that worked well =]

blind elk ---- hmm nah there on the top.. nah havnt replaced the master cylinder but going have too only thing that it can be..

booster shouldnt of shiit it self like that .

mine just is no pressure till u pump it to build it up ie master cylinder just not holidng pressure i think

thanks you both for your input

ill see what happenes 2mrorow

[TKR]

hmmm replaced the master cylinder ... works like a dream =]

cheers all

[Mike__]

good stuff

[Lupes]

Good to hear mate.