TM-9-2350-311-20-1 Maintenance Manual for Volume 1 M109 Hull Download
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TM 9-2350-311-20-1 ITEM NO. 7 8 INTERVAL Semiannual Semiannual ITEM TO BE INSPECTED Engine Fan Drive System Fan Gear Case PROCEDURE Perform backlash test as follows: a. Disconnect both battery ground cables. b. Open air intake grille. c. Mark any accessible blade (5). d. While holding the opposite fan impeller, rotate marked blade as far left as possible. Mark (6) fan housing directly above blade mark. e. While holding opposite fan impeller, rotate marked blade as far right as possible. Mark (7) fan housing directly above the blade mark. f. Measure distance (8) between marks. If distance is over 1 in. (2.5 cm), backlash is excessive. Notify support maintenance. g. Inspect fan for cracked and loose rubber boot and loose retaining ring on boot covering the drive shaft U- joints. WARNING Dry-cleaning solvent (P-D-680) is toxic and flammable. Wear protective goggles and gloves and use only in a well ventilated area. Avoid contact with skin, eyes, and clothes, and don’t breath vapors. Do not use near open flame or excessive heat. The flashpoint for type #1 is 100°F (38°C) and for type #2 is 138°F (59°C). If you become dizzy while using dry- cleaning solvent, get fresh air immediately and get medical aid. If contact with eyes is made, wash your eyes with water and get medical aid immediately. NOT FULLY MISSION CAPABLE IF: f. Backlash is over 1 in. (2.5 cm). g. Cracked rubber boot or loose retaining ring on covers for drive shaft U- joint. 2-27