TM 9-2320-361-20 13-14. FIRST REDUCTION DRIVECHAIN MAINTENANCE (M764) This task covers: a. Removal c. Adjustment b. Installation INITIAL SETUP: APPLICABLE MODELS REFERENCES (TM) M764 TM 9-2320-361-10 MATERIALS/PARTS TM 9-2320-361-20P Clip EQUIPMENT CONDITION Parking brake set (TM 9-2320-361-10). 1. Remove two screws (4), washers (3), and drivechain cover (2) from speed reducer (1) and worm gear housing (10). 2. Remove clip (13), keeper (14), master link (15), and drivechain (6) from drum sprocket (7), idler sprocket (8), and input shaft sprocket (9). Discard clip (13). 1. Install drivechain (6) around idler sprocket (8), input shaft sprocket (9), and drum sprocket (7). If drivechain (6) ends do not meet, adjust drivechain (6). 2. Install master link (15) and keeper (14) on drivechain (6) with new clip (13). 3. Push down on drivechain (6) to measure freeplay at midpoint (5) of drivechain (6). Freeplay should measure 0.5 in. (1.3 cm). If not, adjust drivechain (6). 1. 2. 3. 4. NOTE Perform step 1 if reduction drivechain cover has not been removed. Remove two screws (4), washers (3), and drivechain cover (2) from speed reducer (1) and worm gear housing (10). Loosen jamnut (12) and adjust setscrew (11) until 0.5 in. (1.3 cm) freeplay is obtained at midpoint (5) of drivechain (6) while pushing down on drivechain (6). Tighten jamnut (12) and ensure setscrew (11) does not move. Install drivechain cover (2) to speed reducer (1) and worm gear housing (10) with two washers (3) and screws (4). 13-24