TM-9-1240-400-34&P Technical Manual for M109 Telescopes and Mounts Download

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TM 9-1240-400-34&P Section III. TROUBLESHOOTING 5-6. TROUBLESHOOTING PROCEDURES. a. The symptom index can be used as a quick guide to troubleshooting. Common malfunctions are listed in alphabetical order with a page number reference to the troubleshooting table, where a test or inspection and corrective action are provided. b. The direct support troubleshooting table 5-2 lists the common malfunctions which may be found during maintenance of the M137 telescope mount. Perform the tests/inspections and corrective actions in the order listed. c. The general support troubleshooting table 5-3 lists the common malfunctions which may be found during maintenance of the M137 telescope mount. Perform the tests/inspections and corrective actions in the order listed. d. This manual cannot list all malfunctions that may occur, nor all tests or inspections and corrective actions. DIRECT SUPPORT SYMPTOM INDEX Troubleshooting Procedure (Page) MOUNTING SURFACES Do not seat M115 telescope correctly ........................................................................................................ 5-6 CROSS-LEVEL ASSEMBLY Cross-level control is erratic and rough during movement ........................................................................................................................................... 5-6 Cross-level control exceeds 1.0 mil backlash ............................................................................................ 5-6 Cross-level control requires torque in excess of 11.00 in.-lb (1.24 N-m) to rotate ................................................................................................................... 5-7 LEVEL ASSEMBLY Cross-level bubble or elevation level bubble does not center within 1 graduation................................................................................................................... 5-7 Cross-level vial or elevation level vial has no illumination.......................................................................................................................................... 5-7 COVER ASSEMBLY No illumination in counters ......................................................................................................................... 5-7 5-5