TM-9-2520-238-34 Direct Support for M113 Family Major Assemblies Download
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TM 9-2520-238-34 INTRODUCTION TO HOW TO USE TROUBLESHOOTING 0004 00 PURPOSE The purpose of direct and general support maintenance level troubleshooting is to diagnose carrier problems which are reported to direct and general support maintenance. Troubleshooting tasks in this manual are common to all M113 FOV carriers except where indicated. You should not begin direct and general support maintenance troubleshooting until all operator and unit troubleshooting procedures have been completed. You will perform four actions in direct and general support maintenance troubleshooting: (1) Before starting a troubleshooting task, verify that the reported problem is present in the carrier. (2) After verifying the symptom, find the part that is causing the problem. (3) Replace or adjust that part. (4) Check to make sure the problem no longer exists, and that there are no other problems. DEFINITIONS AND DESCRIPTIONS OF TROUBLESHOOTING PROCEDURES Troubleshooting tasks alwayshave a beginning and an end. You will use task steps, test procedures, indexes, maintenance tasks, and other technical manuals to troubleshoot. Troubleshooting uses the following terms that are not used in other kinds of tasks: 1. FAULT: The part that is not operating correctly and is causing the problem. 2. SYMPTOM: The problem reported to direct and general support maintenance. 3. VERIFY NO FAULTS FOUND: After you have completed the corrective action, you must verify that no faults exist. If the fault condition still exists, then the fault is not fixed or there is another fault. If this happens, start at the beginning of the troubleshooting procedure until you find and correct all faults. Always operate the system and/or carrier to make sure that you have corrected the reported problem. If troubleshooting does not identify a faulty part, the carrier is defective beyond the level of direct and general support maintenance. TROUBLESHOOTING BASICS Troubleshooting Procedure A troubleshooting procedure serves as a starting point for your troubleshooting work. You will branch in and out of procedures as you work to find a fault. Also, you will correct the fault, and check that the fault has been corrected. The parts of a troubleshooting procedure are given below. TM 9-2520-238-34 DIFFERENTIAL MAKES EXCESSIVE NOISE OR VIBRATES WHILE MOVING 0010 00 INITIAL SETUP: Maintenance Level Direct/General Support Tools and Special Tools General mechanic’s tool kit (WP 0034 00, Item 37) Personnel Required Track Vehicle Repairer References See your-20 Equipment Condition Differential removed from carrier (See your -20) Disassemble for inspection per repair differential right angle gearbox (WP 0029 00) Repair output shaft assemblies (WP 0025 00) T TN NO NO YN Y YES 1. Inspect bevel gear backlash to see if it has been adjusted. 2. Has bevel gear backlash been adjusted? 1. Inspect shaft gear bearing to see if it has been adjusted. 2. Has shaft gear bearing been adjusted? 1. Adjust bevel gear backlash (WP 0029 00). 2. Verify no faults found. 1. Adjust shaft gear bearing (WP 0029 00). 2. Verify no faults found. 0004 00-1