TM-9-1240-401-34&P Technical Manual for M109 Telescopes and Mounts Download
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TM 9-1240-401-34&P I 4-21. COUNTER BOX ASSEMBLY (COUNTERS) MAINTENANCE INSTRUCTIONS - continued I c. Assembly - continued I 25 26 27 28 29 30 31 NOTE If the counter box assembly has a tapped hole to screw purging valve stem into, nut (7) is not required. Apply sealing compound to threads of nut (7) and purging valve stem (10). Install retaining strap (11), purging valve stem (10), nut (7), valve core (9), and air valve cap (8). If removed, install plug (6). If removed, install two headless straight pins (5). Install cover (3) with related parts on counter box assembly (4) and secure with four new lock- washers (2) and four machine screws (1). Install elevation handwheel (38) (ref. para 4-17). Using elevation handwheel (38), set correction counter (39) to 0000. Rotate elevation handwheel (38) counterclockwise and ensure correction counter (39) attains a minimum reading of 1335 roils. 4-44