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All Prior products are proudly made in the U.S.A.

Bendix - Delco

Bendix Hydro-Boost or Delco HY-Power

Most units are furnished without the mounting bracket. The old bracket nut must be chiseled or cut off as the threads are staked to prevent the nut from backing off (see figure 1.) New bracket nuts are sent with each unit that requires a mounting bracket. Re-install the bracket in the same position and tighten the nut securely. New bracket nut should be re-staked to prevent loosening.

Note: Ford units do not have this type of removable mounting bracket. Most G.M. and Chrysler products do.

Some units are furnished without a push rod. In this case, the push rod in the old unit must be removed. This can be done with a "pry-tool" (see figure 2.) Another method is to put the unit in a vise with the push rod pointing towards the floor. Insert a screwdriver or rod through the eye hole of the push rod, and strike the rod sharply with a hammer. To re-install, lubricate the end of the push rod with water, then tap the end of the push rod lightly with a hammer until it inserts into the bushing and grommet retainer of the unit furnished.

Caution: Hold the push rod straight while tapping with the hammer to prevent damage to the bushing.

Figure 1. Figure 2.
Master Cylinder 1 Master Cylinder 2

Bleeding the Master Cylinder:

  1. Fill the master cylinder reservoir with heavy duty brake fluid.

  2. Do not bleed with the motor running.

  3. If manual bleeding, start at the master cylinder brake lines, or bleeder screws if present. Next, bleed at the combination valve. Then go to the wheel cylinder or caliper farthest from the master cylinder and work up to the closest one.

  4. If pressure bleeding, connect the bleeder ball to the master cylinder reservoir with the proper cap attachment. Open the bleeder screw on the wheel cylinder farthest from the master cylinder. Allow fluid to run until air bubbles stop. Repeat at each wheel cylinder until you work back to the master cylinder.

Caution: Do not mix hydraulic brake fluid with power steering fluid!

Bleeding the HYDRO-BOOST System

  1. Fill power steering pump with power steering fluid to proper level, and allow the fluid to remain undisturbed for two minutes.

  2. Start the engine and allow it to run for a few seconds. Check the fluid level and add power steering fluid if necessary. Repeat until fluid level remains constant after the engine has run.

  3. Raise the front end of the vehicle so that the tires are clear. Start the engine and run at approximately 1,500 RPM. Depress and release brake pedal several times. Also turn the steering wheel right and left, lightly contacting wheel stops.

  4. Turn the engine off, and re-check power steering fluid level in reservoir. If the fluid is foamy, let set until clear of foam. Add fluid if necessary.

  5. Lower vehicle and start engine. Run at approximately 1,500 RPM. Apply and release brake pedal several times and turn steering full right and left.

  6. Turn engine off, and recheck power steering fluid level in reservoir. Add fluid if necessary.

  7. If fluid is extremely foamy, allow the vehicle to stand for one hour with the engine off, and repeat Steps 1 through 6.

Caution: Always be sure the brake is operating correctly before releasing the vehicle.



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Prior Brake Products Inc., P.O. Box 462167, 315 So. International Rd. Garland, TX 75042
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Copyright 1999 - 2006 Prior Brake Products, Last modified:
Friday, October 06, 2006