How to bleed air from the brake pump.

If the fluid drains out of the pump for any reason it needs to be bled to get the air out of the pump before it will build pressure.
The pump will not work with air in it. Damage to the pump could result if the pump is run for an extended period without fluid.

Once the brake pump has been off the car, or ran without fluid, it will be air bound. Sometimes it is referred to as being air locked. You will have to get the air out before the pump assembly will fill with brake fluid.

After you have filled the reservoir with fluid for the first time after you've had the pump off, you will need to provide a way for the air to escape from the pump assembly before the pump will build pressure. The following instructions explain the proper way to do it.

  • Loosen the steel line ('89-'90 models) or fabric line ('88 models) on top of the pump/motor assembly to allow air to purge air from the line.
  • You should have the accumulator screwed on but leave it a little loose to allow air to escape.

pump air purge

Bleed out the air:

  1. Have someone turn the ignition key to the "run" position and the pump will start.
  2. Watch the base of the accumulator and where the line attaches for fluid coming out.
  3. When fluid starts to come out, shut off the ignition key and tighten the accumulator and line.

The pump should now start to build pressure.

You might need to repeat the process if the pump still will not build pressure.

Thanks to Jim Finn, member of the AACA Reatta forum, for this information.

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