10. MODIFICATION PROCEDURE FOR M870A1 BRAKE (BENDIX) (Continued).
(3) Manually adjust brakes as follows:
(a) Rotate adjustment hex clockwise until brake linings are snug against the brake drum.
(b) Turn adjustment hex counter-clockwise 1/4-turn. (Approximately 70 pound-feet of effort is required to over-
ride automatic adjusting mechanism.)
(c) Refer to Figure 37. Pull brake chamber push rod to confirm that approximately 1/2-inch of free stroke exist.
(4) Uncage spring brakes (if necessary).
(a) Apply 90 to 95 psi air pressure from towing vehicle air gage. Make and hold full brake application to check
that brake chamber push rod stroke is below the re-adjustment limit of 2 inches.
b Repeat steps 1 0.s.(2).(d). through 1 0.s.(4). as necessary, threading adapter an additional 6-inch each time,
to bring brakes in to proper adjustment,.
Serviceability Testing (Leakage Test).
(1) Test and check brakes for serviceability as follows:
(a) Connect air brake system to towing vehicle (Refer to TM5-2330-378-14&P).
(b) Coat all drain cocks, pipe plugs and air line connections, affected by this modification, with soapsuds.
(c) Check all drain cocks, pipe plugs and connections for leakage. No leakage is permitted.
(d) Tighten all leaking connections as required and perform serviceability testing until no sign of leakage
(2) Correct any problems found during above tests, then retest as needed.
q. Reinstall Tires and Remove Jackstands. Refer to TM 5-2330-378-14&P.
END OF TASK.
12. WEIGHT AND BALANCE. Calculated for one trailer. Data plate is applicable to all trailer with this modification.
13. QUALITY ASSURANCE. QA is assured with final inspection. This MWO defines tests, proven parts, and specific
installation directions to convert an M870 or M870A1.