TM-9-2320-279-20-1
M977 SERIES, 8x8 HEAVY EXPANDED MOBILITY TACTICAL TRUCKS (HEMTT)
TECHNICAL MANUAL; MAINTENANCE INSTRUCTIONS; ORGANIZATIONAL MAINTENANCE, VOLUME 1 OF 3
TM-9-2320-279-20-1 - Page 141 of 985
TM 9-2320-279-20-1
Troubleshooting Index (Cont)
Table 2-8. Troubleshooting Subject Index (Con t)
Subject
Vehicle System
Pane
Noisy compressor operation
. . . .
. . . . . . . . . . . . . . . . . .
.....
Air
.................
Noisy drive axle . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . .
. .
. . . .
. . .
Front and Rear Axle
Tandems.
..........
Noisy or vibrating propeller shaft or U-joints . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . .
propeller shaft and
Universal Joints .
...
. .
Noisy transfer case
. . . . . . . . . . . . . . . . . . . . . . . . . .
. .
. . . . . . .
. . . . .
. Transfer Case .
......
Oil leaks in case area .
.................................
Transfer Case .
......
Oil pressure low .
......................................
Engine .
............
One or more hydraulic circuits not working . . . . . . . . . . . Hydraulic .
..........
One or more lights not working (warning or service lights) . . . . . . .
. Electrical .
..........
Outrigger cylinder will not retract .
.....................
Material Handling
Crane (M983) .
.....
. .
Outrigger operation slow or abnormal or outriggers will not extend or
retract .
.....................................................
Material Handling Crane
(M977, M985, M984El)
Overheats .
...................................................
Engine
. . . . . . . . . . . . . . .
.. . .
Parking brakes will not apply at front axle (M984El) .
............
Dual Air Brake . . . . . . . . .
. .
Parking brakes will not release at front axle (M984El) .
...........
Dual Air Brake . . . . . . . .
. .
Power Takeoff Switch (PTO) will not engage .
....................
Electrical
. . . . . . . . . . . . . . . . . . .
..
2-116
Pressure build up slow
.........................................
Air . . . . . . . . . . . . . . . . .
.... .
Pressure drops over 25 psi at gage when brakes are applied .
......
Dual Air Brake . . . . . . . .
.. . .
Pressure drops rapidly after engine shutdown .
...................
Air . . . . . . . . . . . . . .
.......
.
Primary pump makes excessive noise .
..........................
Tanker
. . . . . . . . . . . . .
.... . .
Rear axle tandem out of line or not tracking properly .
............
Suspension
.............
2-155
. 2-124
2-123
2-63
2-153
2-120
2-196
2-197
2-64
2-173
2-174
2-134
2-169
2-139
2-239
2-161
Remote controller will not operate crane or operates abnormally. . . . . .
Material Handling Crane
(M977, M985, M984El) . . .
2-204
2-138
2-156
Retriever system will not lift load, will not lower load, or will not
center tow cylinders (M984El) .
...............................
Retriever .
.................
2-208
Safety valve fails to release system pressure at 150 psi (1 034 kPa) ,
Air .
.......................
2-140
Service brakes fail to release or release slowly .
...................
Dual Air Brake .
............
2-168
Service lights not working .
.....................................
Electrical .
.................
2-120
Slips out of gear or operates abnormally .
........................
Transmission .
..............
2-159
Spring brakes will not apply .
...................................
Dual Air Brake .
............
2-169
Spring brakes will not release
..................................
Dual Air Brake .
............
2-171
Steering wheel does not turn fully in either direction .
............
Steering .
..................
2-152
Stoplights do not work .
........................................
Electrical .
.................
2-122
Sudden increase in effort to turn steering wheel .
.................
...................
2-150
Swing
operation slow or abnormal in one or both directions . . . . .
Steering
Material Handling Crane
(M977, M985, M984El) . . .
2-203
Switches do not work .
.........................................
Electrical .
.................
2-131
Throttle treadle accelerates engine but no air pressure in remainder
of air system .
...............................................
Air .
.......................
2-146
Tires unevenly worn .
..........................................
Wheels and Tires .
..........
2-174
Trailer electrical system does not work .
.........................
Electrical .
.................
2-132
Transfer does not shift into high or low, or slips out of gear .
.......
Transfer Case .
.............
2-155
Transfer case will not lock up
..................................
Air .
.......................
2-144
Change
3
2-57
Back to Top
