rear brakes won't bleed

I"m back yet again with more problems with this truck. It a 1997 gmc sierra that blew a rusty brake line and now I can"t get it to bleed correctly. It will stop the way it is but the pedal almost goes all the way down. Before the line blew the pedal had very little movement and was very responsive. I would like to get it back to being that way but have read that it needs to be hooked to a scan tool to open the ABS to bleed the air out of there but have also read that that doesn"t always work. To bleed it I cracked the lines at MC, then input into ABS. then output, then rr and lr. Is it possible to just get the abs out of the way of the rear brakes. Unhook the rear brake lines and hook them together, plug the ABS and pull the fuse, so as to still have the front routed through there for simplicity. There is really no need for the ABS as I"ve had more close calls with it than with Safari van without it. Obvoiusly I"m cheap and don"t want to pay to have the tool hooked to it. I"m not so much asking if it"s recommeded, but whether it would affect braking performance other than there being no ABS. Will it damage the abs unit to not be in use if no dirt can get in? Or am I missing somewhere air is/can be trapped.

You still got air in the lines need to bleed all four.You can just gravity bleed if you got the time.
start with the right front,left front,right rear,left rear.
never mind the ABS,no need for the scantool.
if you want no ABS,pull all connectors out at the brake pod,or just pull the fuse.But pulling the fuse disables the cruise as well.

Try backing up as steep of incline as you can,open the back bleeder screws or better yet take the lines loose if possible[air will go to highest point] and let set 12 to 24 hrs.then let some one press the brake and hold it [do not pump] till you tighten them up.

how would the front get air in them? i cant bleed the fronts being the bleed screws are seized

Using a bleeder has worked for me, suck the fluid thru and the air.

Can buy a inexpensive plastic one at most autoparts stores, you can do it all yourself which was a big plus for me.

L.

If you have'nt bleed the front calipers, that is your problem. Once that line blew, it allowed air into the system, which when the fluid was pull back to the proportioning valve/ABS module, it allowed air to get into the system. There is no way to get the air out unless you bleed the fronts. I have never had to take a vehicle to get the ABS bleed. Only on one have I had an issue, but was because the ABS module was bad. Front calipers aren't that expensive. You can get them here at Carquest for under 30 bucks. Cheap insurance when it comes to stopping.

My 1996 Chevy Z71 blew a rusty brake line as well. We had a terrible time bleeding it after that. You will need to bleed them all, starting the FARTHEST from the Master Cylinder-RR, LR, RF, LF. We finally got mine nice, but thought the ABS was not allowing them to bleed, but had to do nothing with the ABS to get it, just had to bleed them alot longer than we thought necessary.

farmer boy,
i had a 92 with the same mc. if you got air in the mc it had to be bench bled. the angle of the mc in the truck will not bleed out completly. your parts man can explan better than i can. if you can't bleed the front bleeders you might try to loosen the lines. carefull you don't twist off the lines. good luck. wally

As mentioned ,bleed all 4 forget about ABS . Try tapping on stuck bleeders with small hammer as you try to open them with a wrench. Sometimes lil heat helps. If not ,calipers are cheap .. Brakes,,the most important thign on a vehicle !

We used to heat bleeder screws red hot and douse with cold water,then they would come out. I've loosened them with an impact driver and a tiny wrench slipped over the end of the driver,as the impact was shaking the screw,I smacked the little wrench with a hammer and it all breaks loose. Most bleeder screws will turn out if you get the correct size socket to fiit over them..once you have chewed them up you need the blue wrench and some cold water.

well for one thing it takes two people to bleed the brakes, unless you have a bleeder hooked to it.just cracking the line will do nothing.first thing to do is remove the bleeders as they are most likly plugged with road grit.use a drill bit and air to clean them out.you need a person to apply the brakes when bleeding. once ready get the person to step on the pedal, then you open the bleeder and close it and watch for air discharging out.then he releases pedal and depresses it again and you repeat procedure till you have only fluid shooting out. your descripion of bleeding lines makes me believe thats why you cant get the air out.dont forget to keep the fluid level topped up.

You need a pressure bleeder to bleed ABS, can't be done any other way.
I can't imagine it'll be all that expensive to have somebody do the bleeding.
Think of it this way, how much time have you spent mucking with it and how much is your time worth?
Alternately if you'll be doing a bunch of ABS systems the pressure bleeder is probably worth it.

neat lil helper eliminat0r trick . plastic pop bottle 1/3 full of brake fluid , cut hole in top , use rubber or plastic hose that just fits snug on bleeder , other end submerged in fluid in bottle, open bleeder, slowly pump brakes till bubbles in bottle stop , close bleeder .

Another 'helper eliminator' trick. I am a carpenter, so have several 24" clamps. They will squeeze, but will also spread. I set them up to spread, pump the pedal, squeeze with the clamp, release the bleeder. Also works great for checking for those pesky burnt out brake light bulbs!

I had someone in the truck pumping the brake pedal as you described. Just no luck at it. I have fluid flowing out steady, doesn"t change anything.

Are the front and rear brakes not completely seperate systems? If air can get into the front brakes from the rear brakes that means fluid can get out and there's no point to having seperate systems. No?