ABS bleeding

[lduke88]

I recently fixed some brake leaks on my '95 MTX, but when I tried to bleed the brake lines I got virtually no pressure at the rear wheels. On top of this, in anything but slow traffic heavy breaking causes the ABS pump to cycle slowly. Do I have air in the ABS pump that just won't come out or what? If so I've heard that the only real way to fix this is with a Ford mechanics' module which plugs into the top of the ABS pump computer... is this true? Or can I just pressure bleed the system?

 

[Shoaz]

If the ABS is cycling, it'll likely cycle out any air that's in the ABS pump. If the brake pedal is not soft or long or doesn't require pumping to get pressure, then you probably don't have an air bubble problem, anyway.

The rear brake pressure problem may be related to the bias valve in the rear suspension OR collapsed rear flexible lines. If you had the rear suspension in the air during bleeding, this can cause the bias valve to close and reduce the pressure to the rears. Put a jack under the left rear wheel and elevate it to open the bias valve if you have the rear wheels in the air during bleeding.

 

[SHOZ123]

I always bleed my rear brakes with the motor running so I have the power assist.

 

[itwonder]

It's difficult to bleed the SHO unless the master cylinder is level, which requires getting the rear end way up in the air. I back mine up a bank in front of the house for bleeding. The bias valve and rear hose comments are right on.