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longhorn
09-23-2012, 06:41 PM
I put new brakes , rotors and calipers on my Chev 1 ton, was easy once i got into it and everything went back together easy but now ...................
I cant seem to get the brakes bled?

Got wifey pumping them up and holding them while I open bleeder screw then close it again after they got down.

Well shes got a sore leg and getting grouchie and Ive used a quart of fluid,
What am i doing wrong?

Maybe keep doing it , I changed both calipers ?

Help wou;d be appreciated i need truck tomorrow , thanks.

crimsen
09-23-2012, 07:49 PM
how are they not bled? pedal is still squishy, no braking, no fluid?

longhorn
09-23-2012, 08:42 PM
Pedal squishy.
I drove it and it will stop but not very good.

procircuit
09-23-2012, 08:54 PM
Bleeder at the top?

4skin
09-23-2012, 09:18 PM
tripped the proportion valve while bleeding the brakes might have to crack a rear bleeder and press the pedal till you feel a click

longhorn
09-23-2012, 09:22 PM
tripped the proportion valve while bleeding the brakes might have to crack a rear bleeder and press the pedal till you feel a click

My neighbour just told me pretty near the same thing.
He said something about a splitter ?

He also said maybe i gotta bleed back brakes too.

Ill try that in the morning.

crazylike
09-23-2012, 10:49 PM
you should always start with the rear brakes even if you don't work on them... start back pass side then rear driver then front pass then front driver side.

crimsen
09-24-2012, 11:42 AM
proportioning valve may be it, but usually that would result in no braking to front or rear wheels. the proportioning valve is normally to stop brake fluid from going to the front or rear in the event of a failure causing loss of fluid. works on the principal of pressure on the sealed side will be higher, which forces a valve closed on the low pressure side. normally the pressures will balance each other out and the valve will kinda just "float".


i suspect there is still air in the lines. can try gravity bleeding them by cracking the bleeder screws and just keep adding fluid as it flows out. some people have a belief that by pumping the pedal and holding, it will agitate the brake fluid and get air inside it. i know it's the way we were all taught to pump the pedal 3 times, holding on the third, and then crack the bleeder screw.



one other issue that may be present, is depending on how old the vehicle is, it may not be sealing properly. if you think the inside of the pistons, when new and full they are fully extended. as they wear and move down, the part that was covered under full is now exposed. this allows it to corrode possibly. now that you have filled and gone back to new, you may now be trying to seal on a part that is partially corroded.



in going with the spirit of what crazylike said, although his actual words are wrong, is proper bleeding is done starting on the brake which is the farthest from the master by the path the fluid travels.

if you look at something like an 85 toyota PU, the brake line to the rear runs down the passenger side frame rail. and goes to the axle on the passenger side. this places the rear drivers as the longest path fluid has to travel and is the one which should be bled first. in my case its LR>RR>RF>LF, not RR>LR>RF>LF.

crazylike
09-24-2012, 01:38 PM
i work on american vehicles mostly, and they are all rr,lr,rf,lf, but yes you are correct Crimson you should always start with the furthest from the master. (you should check your words as your english is incorrect. you don't need that first IS after the word wrong..)
i figure since he doing a chevy then i would give him the info to do a chevy, dodge, ford or jeep. i didn't think the way to bleed a toyota would pertinant information as he working on a chevy... why confuse the guy???
as for the proportioning valve it will or should reset itself when you bleed the brakes back to front...

crimsen
09-24-2012, 01:49 PM
yes, for the chevy it is RR LR RF LF. i just wanted to make the distinction that for bleeding brakes, the best answer is farthest from master first. there are people who would read it that RR,LR,RF LF is the proper way so that applies to all vehicles, including imports.

i know i deal with enough people in my industry (alarm and security) that think "hey, i seen they have this camera that works well at night. i bought some other camera and it does not work well at night. can you fix it?" drives me up the wall.

longhorn
09-24-2012, 05:31 PM
Its a 2000 Chev 1 ton flatdeck.

Bled one back brake and they work fairly well now.
I bled the wrong one it looks like i did the lr Ill do the rr tonight.
Thanks for the help all..........................