TM 1-1520-238-T-5
Change 5
7–79
7–21.
UTILITY HYDRAULIC SYSTEM – MAINTENANCE OPERATIONAL CHECK (cont)
7–21
NOTE
If referenced out of one paragraph or volume into another for additional
troubleshooting, upon completion of the task, return to the maintenance
operational check for the original paragraph or volume.
1. Perform visual check of utility hydraulic system with AGPU operating (TM 1-1520-238-PMS). Replace any
leaking component (TM 1-1520-238-23).
(a). If hydraulic fluid is leaking from drilled passageway/port forward of utility hydraulic manifold about one
inch below dirty filter indicators, replace indicator packings (TM 1-1520-238-23).
2. If rotors begin to turn when utility hydraulic external power is applied, replace utility hydraulic pump outlet
check valve (TM 1-1520-238-23).
3. Do not close access doors or install access panels until maintenance operational check is completed.
4. Remove external pressurized air and utility hydraulic power (TM 1-1520-238-23).
WARNING
The hydraulic system is pressurized to 3000 psi. Be certain that trapped
hydraulic pressure is released before loosening any connections. Failure to
do so could result in death or serious injury. If injury occurs, get medical
aid immediately.
NOTE
Total utility system fluid volume is 2.60 gallons.
5. Drain utility reservoir to refill level, if required (TM 1-1520-238-23).
NOTE
Decal on access door R325 shows proper positioning of selector valve of
hydraulic hand pump.
Refer to figure 7–34 for location of hydraulic hand pump selector valve.
6. Set hydraulic hand pump selector valve (fig. 7–34), to OUTBOARD position.
