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Brake Proportioning/Combination Valve: Testing and Inspection

Proportioning Valve

Inspection






1. Remove the front brake tube (B) and rear brake tube (C) from the master cylinder (A).
2. Connect two pressure gauges (D); one to the output valve of the front (B) and rear (C) brake.

Note: Be sure to bleed the system after connecting the pressure gauges.

3. With the brake applied, measure the front pressure and the rear pressure.

Graph:






If the measured pressures are within the specified range as illustrated, the proportioning valve is good.

4. Reconnect the brake lines in their original positions and bleed the system.

Chart:






Note: This table shows characteristics of the proportioning valve as the pressure increases.