10. MODIFICATION PROCEDURE FOR M870 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
override automatic adjusting mechanism.)
(c) Refer to Figure 20. Pull brake chamber push rod to confirm that approximately 1/2-inch of free stroke exist.
(4) Uncage spring brakes (if necessary).
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.
Repeat steps 1O.s.(2).(d). through 1 0.s.(4). as necessary, threading adapter an additional 1/16-inch each time, to
bring brakes in to proper adjustment, .
Serviceability Testing (Leakage Test).
Test and check brakes for serviceability as follows:
(a) Connect air brake system to towing vehicle (Refer to TM5-2330-360-14&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 occurs.
Reinstall Tires and Remove Jackstands. Refer to TM 5-2330-360-14&P.
END OF TASK.
10. MODIFICATION PROCEDURE FOR M870A1 BRAKE (BENDIX)
To prevent Injury to personnel or damage to equipment, place Jack stands under rear
axle before removing wheels.
Remove Rear Wheels. Refer to TM 5-2330-378-14&P.
(1) Drain all air reservoir tanks.
Before starting to loosen ten lug nuts on wheels, check lug nut stampings to determine the
direction of rotation of nuts.
(2) Install jack stands and remove rear wheels.