TM-9-2350-358-BD M109A6 Battlefield Damage Assessment and Repair Download
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TM 9-2350-358-BD 7-7. BRUSH, ELECTRIC, MOTOR/GENERATOR, WORN - CONTINUED 5. Using a hacksaw or other suitable tool, open battery to expose carbon core. 6. Clean and cut a piece of carbon core and shape to fit the brush holder. 7. Insert the piece of carbon into the brush plate and position the loose end of the old brush wire between the carbon and the retaining spring to ensure electrical continuity. 8. Seat the brushes as follows: a. Cut a strip of abrasive paper slightly wider than the commutator surface. b. Tape the strip of abrasive paper over the commutator. c. Install the brush holder with piece of carbon core enclosed. d. Rotate the armature in the normal direction until the piece of carbon core face conforms to the armature surface curvature. e. Remove the abrasive paper and blow the armature commutator area free of dust and grit. 9. Reassemble generator and test for proper operation. 10. Reinstall and align generator. 11. Set MASTER power switch to ON. 12. Record BDAR action taken. When mission is complete, as soon as practical, repair the equipment/system using standard maintenance procedures. SECTION III. SWITCHES, RELAYS, AND SENSORS 7-8. GENERAL Special switches, relays and a sensor which are used to apply power to activate a circuit or subsystem are covered in this section. 7-9. SWITCH, RELAY, OIL PRESSURE-ACTIVATED, AIR CLEANER AND GENERATOR SYSTEM General Information: The air cleaner and generator system, oil pressure-activated relay switch is a safety interlock switch, which opens when oil pressure drops below a SAFE level. Under extreme conditions when system operation must be maintained regardless of excessive wear and/or damage to the engine, the switch can be bypassed. CAUTION The oil pressure-activated interlock switch opens when oil pressure drops below a predetermined SAFE level. Bypassing the Interlock switch allowing the engine to continue to run, will cause excessive wear and eventual engine failure. 7-9