No or Low Pedal Testing of Prop Valve

February 24th, 2009



No or Low Pedal Condition Testing of Combination/Proportioning Valve

STOP! Bleed master cylinder before installation. Use supplied kit enclosed.

  1. Using test light, attach clip to a positive and touch the point of the tester to the electrical connection of the combination valve.
  2. If NO light goes on, the valve system is operating correctly. No further testing is required.
  3. If light goes on, this indicates the pressure differential valve in the combination valve is stuck in front or rear position.
  4. Bleed brake system to determine which system, front or rear is not getting proper flow of fluid; one system will squirt  out of bleeder, other system will trickle out.
  5. The system with the flow must be opened for flow to alter the pressure on opposite side of pressure differential valve   to center valve.
  6. Slowly depress pedal with steady pressure until light goes out. When light goes out, close bleeder.
  7. Your system is now centered. Bleed complete system following enclosed bleeding instruction.

I’m doing a Disc Brake Conversion and need to add the correct valving. What do I use?
The valving associated with braking falls into four basic categories:

  1. Metering Valves: Used in the disc portion of a disc/drum system to hold off the application of the discs slightly allowing the drums to catch up. This provides rear stability on wet surfaces and reduces front pad wear.
  2. Proportioning Valves: Used in the rear to decrease the rate of pressure rise to the drums. Relative to pedal force as weight is shifted to the front during braking. This prevents the rear from locking up. Proportioning Valves are available either in a preset or adjustable configuration.
  3. Residual Pressure Valves: Used to hold a residual pressure in your system. You will require a 2 lb to the discs if the master cylinder is lower than your calipers and a 10 lb to the drums to prevent air ingestion when the brakes are released.
  4. Combination Valves: These valves provide metering to the front PLUS proportioning and residual to the rear. This is   the recommended valve for all front disc brake conversions. Available for: GM, Fords, Chryslers and Jeep.










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