TM-9-2320-387-24 HMMWV Direct Support & General Support Maintenance Manual Volume 1 Download
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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 45 to 40 mph (72 to 69 kph) on dry concrete road and apply sufficient pressure to lock up front brakes. If rear brakes lock up before front brakes, the proportioning valve should be replaced. Replace proportioning valve (para. 7-10). Method for checking hydra-booster: Depress brake pedal several times to exhaust accumulator pedal. Depress brake pedal and start engine. Brake pedal should fall, then push back against operatoh foot. Replace hydro-booster (para. 7-6). Replace service brake pedal (para. 7-9). The steering tests will check for suspension problems that will affect braking. TM 9-2320-387-24-l BRAKE SYSTEM HYDRO-BOOSTE PB~P~BTIONING VALVE BRAKE PEDAL BUSHING 2-429