I had removed the rear calipers and master cylinder and all the brake parts under the hood while i had it painted and swapped in the new rear end. I connected everything back up and filled the res with new fluid, opened the rear bleeder valve and proceeded to bleed it and i pumped on the pedal, it had pressure but it didn't bleed anything, the fluid stayed at the same level. Whats going on here? is there some other valve for the rear brakes im missing here or what?

I also got another question, the differential fluid is 90 weight right?

 

my book says 80 weight in the differential

 

How long was the master cylinder and/or slave cylinder sitting w/o fluid? My guess would be the piston that is inside has become stuck. That would be my best guess. After you took the master cylinder out, I'm assuming that you poured out the brake fluid also. Well, the brake fluid (when it was in your car) prevented the internals from rusting. Well, to be truthful, the brake fluid was slowly picking up water from the atmosphere, but it slowed down the rusting of your internal brake components.



Anyways, I'm assuming that since you left it out, it may have gotten clogged by the dirt/rust settling along the edges of the piston, causing it to not pump your brake fluid. Disassemble your master cylinder (IF you know how). If not, have someone look at it. Bench bleed before reinstalling.



See if that helps your problem.



If not, check the brake lines and the calipers themselves.

 

did you bleed the master before you put it in? if theres air in the master, it wont pump anything.



mike

 

nope, so how do i do that?

 

The same way you bleed the calipers, except (I believe) you have to use a line wrench and loosen/tighten the hard lines to do it. I don't think there are any bleeders on the master cylinder. I don't remember.



Put down lots of rags since you have new paint.

 

I always bench bleed my master before putting them on...

This may be hard to belive..when I changed my master like 5 months ago ..I Bench bleed the master and didnt have to bleed the line...

 

The easiest way to bleed a master cylinder is to put some tubes on the holes where the fittings go, and loop them back up into the reservior. Fill the reservior, and with a screwdriver (or anything long and skinny that won't damage the master, be careful not to scratch the inner walls of it!) reciprocate the piston slowly until you see no more bubbles coming out of the tubes you've looped into the reservior. Keep the tubes under the brake fluid level in the reservior or you might suck air back into the system. After it stops releasing any air from the tubes remove them (with the piston in it's resting (out) postiion!) and cover the reservior... put some clean rags under the master etc so you don't drip brake fluid on your paint etc and go put it on the brake booster... then hook up the lines. Use flared line wrenches whenever messing with these fittings or you are more likely to round them off. After that you just bleed the rest of the system like you normally would. You will have quite some time before the lines are full of fluid if they were drained, you might want to flush it also so have alot of fluid handy. The easiest/quickest way to do this is to get the vacuum pump + brake bleeding kit, the local ghetto 24 hour store meijer has these for like $30... then you can just suck the brake fluid down through the system from the reservior from the brake calipers bleeder valve.

 

what a fuc*(g joke, gonna risk my new paint for this too. :rant:

 

Thats what I did on my fiero when I installed the 12"/4 piston brake kit. Although I'm pretty sure I still bench bled the master... force of habit. If you pick up the vacuum kit it will be alot easier, and you'll use it all the time when bleeding brakes in the future, makes it a breeze... and eliminates alot of mess.