Brakes

[tolon]

Hey, I've just got done replacing almost my entire brake system in my '92 Explorer, (IE, Master Cylinder, Rear Wheel Cylinders, Front and Rear Brake pads and shoes, Rear drums, and the RABS Valve) Anyway, Ive spent the last 3 days trying to bleed the system, ( I did bench bleed the MC before Install) and after each time the brakes feel almost normal, but within 2-3 hours whether sitting unused or being driven, the brake system light in the dash will come on and my brakes stop working. The MC resevoir does not loose any fluid, and I have checked all the lines for leaks, and like I said, I have attempted to bleed the brakes (right rear first then LR then RF then LF, just like it said in the Haynes manual), going through almost a gallon of brake fluid, but I am stumped. I'm not really seeing any air when I bleed anymore, but it seems to help for a little while anyway. Is there anything "special" that I need to do when I bleed the brakes, or is there somewhere else I should check. Anything would help.
Thanks

 

[MAXIMIS1]

DO YOU have ABS? (anti-lock brakes). and how well did you bench bleed the m/c and was it re-manif. or a new part? nm on the abs {rabs}didnt see at first

 

[MAXIMIS1]

also rear shoes should be adj. right up against drums almost to point of not wheel not turning.

 

[tolon]

DO YOU have ABS? (anti-lock brakes). and how well did you bench bleed the m/c and was it re-manif. or a new part?

Blead the MC for avout 20 min making sure there were no air bubbles for about 5 min. it was a new part, not reman. Did a search and found this posted earlier:

Here's the FORD manual without pics...


1. On the master cylinder, loosen the master cylinder-to-hydraulic line fittings.

2. Wrap a shop cloth around the tubing below the fitting to absorb escaping brake fluid.

3. Push the brake pedal down slowly to the floor of the cab. This will force air trapped in the master cylinder to escape at the fitting.

4. Hold the pedal down and tighten the fitting. Release the brake pedal. Do not release the brake pedal until the fitting is tightened or air will re- enter the master cylinder.

5. Repeat this procedure until air ceases to escape at the fitting.

6. Place a box wrench on the bleeder fitting on the Rear Anti-Lock Brake System Valve. Attach a rubber drain tube to the bleeder fitting making sure the end of the tube fits snugly around the bleeder fitting.

Submerge the free end of the tube in a container partially filled with clean brake fluid. Loosen the bleeder fitting approximately three-quarters of a turn.

Slowly press the brake pedal all the way down. Close the bleeder fitting, and return the pedal to the fully-released position. Repeat this operation until air bubbles no longer appear at the submerged end of the bleeder tube.When the fluid is completely free of air bubbles, close the bleeder fitting and remove the bleeder tube.

7. Place a box wrench on the right brake wheel cylinder. Attach a rubber drain tube to the bleeder fitting making sure the end of the tube fits snugly around the bleeder fitting.

8. Submerge the free end of the tube in a container partially filled with clean brake fluid. Loosen the bleeder fitting approximately three-quarters of a turn.

9. Slowly push the brake pedal all the way down. Close the bleeder fitting, and return the pedal to the fully-released position. Repeat this operation until air bubbles no longer appear at the submerged end of the bleeder tube.

10. When the fluid is completely free of air bubbles, close the bleeder fitting and remove the bleeder tube.

11. Repeat this procedure at the left brake wheel cylinder on the opposite side. Refill the master cylinder reservoir after each wheel cylinder is bled.

12. Bleed the front brakes starting with the right front brake and then the left front brake as described in Steps 7-11 of this procedure.

When the bleeding operation is complete, fill the master cylinder to the maximum level line of the master cylinder reservoir.

 

[tolon]

I did adjust the rear drums, All I can figure is that there is air trapped in the RABS valve, since I just didn't bleed it. (didn't know I was supposed to until now - Stupid repair manual didn't say anything about it.) so I'll have to give that a try.

 

[Creager]

So THATs how you bleed that thing...

im gonna try this tonight

 

[ThespecialistKC]

I just went through this whole fun scenario so let me add my 2 cents..... bleed everything just as stated above... but FIRST disconnect the battery. I'm not 100% sure, but I think the computer monitors the rear brake pressure somehow, possibly in the RABS valve. If it detects a loss of pressure it automatically shuts down the rears to prevent total brake loss. I went through everything on all 4 corners, but couldn't get the rears to bleed. Changed out my crudded up RABS valve, everything starts to bleed fine, then instant pedal again with nothing out the rear bleeder valves. WTF? Look at the manual again, it states one should disconnect the battery first. Did that, rears bleed fine, everything looks good.
I may be way off base, but that's what happened with me last weekend. Good luck and let us hear back from you....

KC

 

[tolon]

Will do, I'm going to try bleeding it again tonight, and (crossing my fingers) hopefully this should do it.