bleeding brakes with anti lock

[DShattler]

I installed one ton rear wheel cylinders on my 95 3/4 ton with four wheel drive and anti lock brakes. I bled the wheel cylinders starting from the right rear and worked forward ending at the front left. The brakes will not hold pressure and bleed down. What did I screw up? Any help would be apprecitated.




95 Dodge 3/4 4 wheel drive, Banks turbo kit, Mag tech transmission pan. 160,000 miles and still pulling good.

 

[Extreme1]

If nothing is leaking, your master cylinder is going. Did the fluid look nasty? Try bleeding until clean. Sometimes a chunk of crud will get hung up and cause an internal leak. More bleeding might heal it.

 

[HEYBOSS]

Bleeding Brakes

There's a couple ways maybe more to bleed brakes, some works better than others. TRY this First. Make sure brakes and wheel cylinders are properly installed. Also make sure rear brakes are adjusted properly. Make sure master cyl. is full. Open one rear bleeder and leave it open, have an assistance slowly push the brake pedal down and HOLD it. Close the bleeder and then slowly release brake pedal, Wait a few seconds and repeat this procedure two more times. Then do the same to the other rear wheel cylinder and then do the fronts. Check master cylinder often to make sure you don't run out. This is one procedure and there's more. Hope it works, if not report back.



Don't know if you have posi rear end (LSD) If you do, make sure you don't adjust one wheel to tight, they should be adjusted iqually and not overtight, Damage to rear end could result.

 

[illflem]

Sometimes this problem develops after bleeding brakes due to pushing the brake pedal down further than it travels in normal braking. The master cylinder piston can be rusted in the normally unused portion and tear up the seals when pushing the pedal all the way to the floor. Master cylinder rebuild may be in order. In the future avoid this by not flooring the brakes while bleeding or use a pressure bleeder.

 

[DShattler]

Thanks for the information. I will try bleeding them again with the information you have given me. I was wondering if the proportioning valve might have moved and is letting some of the fluid get past it. I should have save the artlicle I found in TDR on installing the one ton rear wheel cylinders. Thanks again.

 

[Dave Fritz]

If you have 4wheel ABS, make sure you are bleeding the brakes correctly. Depending on which technique you are using, there is a metering valve that may have to be held open. See TSB05-03-94 for the procedure.



Dave

 

[Eric_77]

One thing that seemed to be overlooked in directions on bleeding be sure any time that the bleeder is open that MC has pressure applied to it. Push on pedal, open bleeder, close bleeder, release pedal.



I always use clear line to watch for bubbles coming out of cylinder. Be sure to use 2 foot or so, so that line is lower than cylinder and into a cup with some brake fluid in it. keeps air from being sucked back into cylinder.



Be sure to get good fluid like DOT 4 or 5. 1 Do NOT use DOT 5 it will ruin the system.

 

[DShattler]

I want to thank everyone for the suggestions and the information. I found out that my master cylinder was bleeding by so I replaced it. Thanks again.