TM 10-3930-659-20 Table 4-1.  Mechanical Troubleshooting (Con't). MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION Step 3. Test fork/brake hydraulic pump flow (see paragraph 17-2). Replace damaged fork/brake hydraulic pump (see paragraph 17-5). Step 4. Test right and left brake valves for leakage (see paragraph 10-6). Replace defective brake valve (see paragraph 10-9). Step 5. Inspect service brake disc (see paragraph 10-7). If service brake disc is damaged, notify Direct Support Maintenance. Step 6. Inspect brake system for leakage by removing differential fill plug and checking for overfilled dif- ferential.  Apply service brakes and check for leakage from fill plug. If differential oil leaks from fill plug, notify Direct Support Maintenance. 21.  BRAKES DRAG. Step 1. Inspect right and left brake pedals for free movement. Remove any debris preventing pedal movement. Step 2. Inspect parking brake cable for proper adjustment (see paragraph 10-2) or damage. Adjust parking brake (see paragraph 10-2). Replace damaged parking brake cable (see paragraph 10-4). Step 3. Test right and left brake valves for leakage (see paragraph 10-6). Replace defective brake valve (see paragraph 10-9). Step 4. Inspect service brake disc (see paragraph 10-7). If service brake disc is damaged, notify Direct Support Maintenance. Step 5. Check brake drag by driving forklift truck for five minutes. If differential is hot around fill plug, notify Direct Support Maintenance. 22.  BRAKES CHATTER. Step 1. Bleed brake system (see paragraph 10-17). Step 2. Inspect service brake disc (see paragraph 10-7). If service brake disc is damaged, notify Direct Support Maintenance. 23.  HISSING NOISE WITH BRAKE PEDAL DEPRESSED AND ENGINE STOPPED. Test right and left brake valves for leakage (see paragraph 10-6). Replace defective brake valve (see paragraph 10-9). If hissing noise still exists, notify Direct Support Maintenance. 4-18