TM-9-1240-401-34&P Technical Manual for M109 Telescopes and Mounts Download
Page 322 of 344
TM 9-1240-401-34&P 6-12. M42 PERISCOPE FINAL INSPECTION AND ADJUSTMENT- continued d. SEALING INSPECTION 1 2 3 4 5 6 NOTE There are currently 2 production models of the M42 periscope in use. The earlier model re- quires use of adapter 10552433 to attach purging hose assembly. The later model does not require the adapter. Remove machine screw (1) or air valve cap (2) and purging machine screw (3). For early model M42 periscope only, attach adapter (4) to inlet port (5). Attach hose assembly (6) to adapter (4) or to purg- ing valve stem (7). Make sure pressure regulator valve (8) is closed (fully counterclockwise). Open pressure regulator valve (8) until low pressure gage (9) indicates 5 psi (0.35 Kg/cm 2 ). a. Maintain pressure for 5 minutes. b. Close pressure regulator valve (8). Apply adhesive to purging machine screw (3). In- stall and tighten purging machine screw (3). NOTE Early production models go to step 6. Late production models, go to steps 7,8, and 9. Disconnect hose assembly (6) from inlet port (5). a. Remove adapter (4). b. Apply adhesive to machine screw (1). Install machine screw (1) in inlet port (5) and tighten. 6-12