TM 55-1930-209-14&P-13
3-19.2.2.5 Hydraulic power unit
WARNING
Make sure hydraulic power unit is electrically dead before starting repair or
removal. Redtag switchboard circuit breaker P16 (Crane Hydraulic Unit).
3-19.2.2.5.1 Cleaning and inspection
a.
Clean exterior of hydraulic power unit with hot soapy water or with an approved solvent. Rinse thoroughly
and dry with clean cloth or dry with filtered compressed air.
b.
Clean pump motor exterior with filtered compressed air or vacuum. Wipe, using clean cloth moistened with
an approved solvent. Clean terminals and wipe wires with lint-free cloth or with electrician's brush.
c.
Visually inspect hydraulic power unit, including hoses, for leaks, corrosion, cracks, or damage. Repair leaks.
Replace hoses, if necessary. Remove corrosion and touch up paint according to TB 43-0144.
d.
Visually inspect pump motor for burned, bent, loose, corroded, or otherwise damaged terminals. Inspect
wiring for breaks, loose connections, or other obvious damage. Tighten loose connections, replace
damaged terminals, and replace damaged wiring. Touch up paint according to TB 43-0144. Do not paint
threads or labels.
e.
Visually inspect fill cap. Clean, if necessary.
f.
Visually inspect filter element. Replace filter element, if necessary.
g.
Visually inspect level and quality of hydraulic fluid. Add fluid or drain and refill as necessary.
3-19.2.2.5.2 Repair. Repair involves replacement of the filter element and hydraulic fluid as follows:
a.
Turn hydraulic power unit motor controller HAND/OFF/AUTO switch to OFF. Redtag motor controller with:
"WARNING - DO NOT ACTIVATE. REPAIRS BEING MADE."
b.
Remove drain plug from bottom of hydraulic power unit tank and drain hydraulic fluid into bilge tank.
c.
Unscrew filter element.
d.
Install new filter element and make sure it has a tight seal.
e.
Replace drain plug.
f.
Remove filler cap and fill tank with new hydraulic fluid. Fill tank to within 1 inch of top of filler neck.
g.
Replace filler cap and make sure it is tight.
h.
Turn motor controller HAND/OFF/AUTO switch to HAND.
i.
On deckhouse top control panel inside watertight box, push START button on START/STOP control station
(Figure 3-6) to start hydraulic power unit.
NOTE
After filling bow crane hydraulic unit initially, crane movement may be jerky
and erratic until the system works out air in the hydraulic lines.
j.
Operate bow crane by extending all booms to their maximum length, raising them to maximum height, and
slewing crane in a complete circle to the left and then to the right. Continue to operate crane without load
until it runs smoothly in all actions.
k.
Stop hydraulic power unit by pushing STOP button on START/STOP control station on deckhouse top.
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