TM 9-2320-209-20-3-2 (c) Air tube elbow fitting CAUTION Fittings are made of soft brass. They can be stripped if tightened too much. Tighten fittings just enough to stop air from leaking. NOTE The air tube elbow on the right side air tank on truck M764 is used for this typical procedure. 1. Using 3/4-inch combination box and open end box wrench, screw in and tighten elbow fitting (1). 2. Using 13/16-inch combination box and open end box wrench, screw on and tighten tube nut (2). NOTE Follow-on Maintenance Action Required: 1. Start engine and let it run until air pressure gage reads between 65 and 125 psi. Refer to TM 9-2320-209-10. 2. Stop engine. Refer to TM 9-2320-209-10. 3. Do air system leak test. Refer to Part 1, para 1-5. END OF TASK 13-160