TM-9-2320-280-20 HMMWV Technical Manual Unit Maintenance Volume 1 Download
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6"REFERENCE INFORMATION Test for faulty proportioning valve: Drive the vehicle and have an assistant observe during the performance of this test. With vehicle at curb weight, decelerate vehicle from 46 to 40mph (72 to 69 kph) on dry concrete mad and apply sufficient pressure to lockup front brakes. If rear brakes lock up before front brakes, then the proportioning valve should be replaced. Replace proportioning valve, refer to (para 7-18). Method for checking hydrobooster: Depress brake pedal several times to exhaust accumulator pedal. Depress brake pedal and start engine. Brake pedal should fall, then push back against operators foot. Replace hydro-booster, refer to (para 7-14). Replace service brake pedal, refer to (para 7-16). The steering tests will check for suspension problems that will affect braking. TM 9-2320-280-20-1 BRAKES 2-455