Brake bleeding question

JBronco · #1 (**permalink**) 07-02-2009, 03:09 PM

I recently overhauled the brakes on my 90 XLT 5.8. I replaced all parts, including cylinders on all four wheels. I bled the brakes per the shop manual but I've noticed that the master cylinder does not seem to fill up correctly. It looks like it is divided into four "cells" and one of the "cells" only fills about halfway. But the master cylinder is full, well it is topped off anyway. I cannot add any more fluid to it.

Is this normal, or do I need to do something else (bleed master cylinder etc.?). I had a shop bleed the brakes with a pump but it still does this. The brakes work fine, but I want to be sure that the proportion is correct and I do not overuse the front brakes and cause a heat issue with my new rotors. I remember once having a cylinder replaced on the rear passenger side and the mechanic said that you have to bleed the ABS valve any time you replace a wheel cylinder. Is this correct? I am mainly concerned with the brakes proportion being correct and the RABS working properly come winter.

Thanks!

greystreak92 · #2 (**permalink**) 07-02-2009, 09:35 PM

JBronco, haven't heard from you in a while glad to see you.

I am unaware of the need to bleed the ABS portion of the system independently since it is in line with the rest of the hydraulics for the rear axle. As long as you don't allow the fluid level in the master cylinder to drop too far and draw air into the system, the ABS portion should remain completely passive when bleeding.

As for the fill level, I have noticed the "sections" within the reservoir in my 93 with varying levels from time to time and no amount of refilling will correct it. Never had any issues with it, personally.

JBronco · #3 (**permalink**) 07-02-2009, 10:57 PM

Thanks GS, yeah I've been hibernating. I stopped driving the Bronc a lot when gas topped $4 a gallon. So now I'm just taking care of some little issues that I had put off when I wasn't driving it.

As far as the brakes, they are fine. I went back by the shop and they told me it was normal. I guess that I never noticed it before. I tend to ignore master cylinders until they break. But now my whole system is flushed and replaced with DOT 4 and working great. I replaced every single part on each wheel, down to the last spring and washer. New drums, discs, cylinders, etc. etc. etc. The back wheels looked so pretty with all of the colorful new springs etc. that it was almost a shame to bolt the wheels back on!