Brake Proportioning/Combination Valve: Testing and Inspection

NOTE: This operation requires a helper.




CHECK AND ADJUSTMENT OF FLUID PRESSURE



Set rear axle load
a. Set the vehicle unladen.
b. Measure the rear axle load and note the value.
c. Set the rear axle load.

Rear axle load = RW + 100 kg (220 lb)
(Where RW = Rear axle unladen weight, Measurement taken in step b.)




Install the Load Sensing Proportioning Valve (LSPV) gauge, Special Service Tool (SST) #09709-29017, and bleed brake system




Raise front brake pressure to 9,807 kPa (1,422 psi), 7,845 kPa (1,138 psi) And check rear brake pressure
Brake pressure chart in: kg/cm2 (psi,kPa)




NOTE: The brake pedal should not be depressed twice and/or returned while setting to the specified pressure. Read the value of rear pressure two seconds after adjusting the specified fluid pressure.



Raise front brake pressure to 11,768 kPa (1,705 psi), 9,807 kPa (1,422 psi) AND CHECK REAR BRAKE PRESSURE
Brake pressure chart in: kg/cm2 (psi, kPa)







If necessary adjust the fluid pressure by changing the spring length.

- Low pressure: Shorten A
- High pressure: Lengthen A
- Initial set length: 2VZ-EF 167.6 mm (6.598 in.) Others 166.9 mm (6.571 in.)

NOTE: 1 mm (0.04 in.) displacement of the spring length changes the fluid pressure about 98 kPa (14.2 psi).




Tighten the nuts.

Torque: 25 Nm (19 ft lb)




In the event pressure cannot be adjusted by the spring length, raise or lower the valve body.
- Low pressure - Lower
- High pressure - Raise

NOTE: 1 mm (0.04 in.) displacement of the valve body changes the fluid pressure about 7.2 kg/cm2 (102.4 psi, 706 kPa).
Torque the nuts.

Torque: 130kg-cm (9 ft-lb, 13 N.m)



Adjust the fluid pressure by changing the spring length again.
If it cannot be adjusted, replace the valve assembly.