Brake Proportioning/Combination Valve: Adjustments

SEDAN
1. Drive vehicle onto a hoist or alignment machine, so that vehicle is at curb load level and wheels are on a flat surface. Make sure fuel level is at least 3/4 full.

2. NOTE: Do not change position of the upper nut on valve operating rod.

Loosen valve adjuster set screw.





3. Obtain a piece of rubber or vacuum hose or plastic tubing 3/8 inch OD x 1/4 inch ID. Cut a piece 16.3 mm ± 0.3 mm (0.64 ± 0.012 inch) and slice it lengthwise as shown.
4. Place hose or tubing on valve operating rod. Refer to illustration under Step 3.
5. Make sure the adjuster sleeve is resting on the lower mounting bracket and not corroded to the rod. It must move freely when the set screw is loosened. Install set screw. The dimension will position the valve for normal operation. Remove hose or tube.
6. Alternate adjustment / check method: Set an inside veinier caliper to 16.3 mm (0.64 inch) and insert between the nut and grommet. Perform adjustment as above.

If further adjustment is necessary refer to the following procedures:





7. To decrease pressure at rear brakes install set screw in adjuster sleeve in desired position.

To increase pressure at rear brakes tighten set screw in desired position.