TM 9-2320-209-20-3-2 (2) Air tube fittings. (a) Air tube connecting nipple 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 connecting nipple on the left side of chassis of truck M764 is used for this typical procedure. 1. Screw two tube nuts (1) onto adapter fitting (2). 2. Using 11/16-inch combination box and open end box wrench, hold adapter fitting (2). 3. Using 13/16-inch combination box and open end box wrench, tighten two tube nuts (1). 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 13-158