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6. To raise the load manually:
a. The jack is equipped with an adjustable hand pump. The hand pump handle length can be varied
by inserting the quick release pin through the clamp and appropriate hole along the handle (see
figure 4). A longer handle length provides greater pumping leverage for high pressure pump
operation. A shorter handle will increase the plunger stroke and allow more oil pumped per stroke.
This permits a more rapid raising of the jack plunger under a light or no load.
b. Close release valve located on the panel.
c. Operate the air valve or electric motor or hand pump until the ship adapter contacts the jacking
pad. Insure the ship adapter and the jacking pad are correctly mated. The load may now be raised
by operating the air valve or electric motor or hand pump.
d. Do not lift a load greater than the rated capacity of 100 tons.
e. Do not attempt to raise the plunger beyond the rated hydraulic lift (72 inches maximum).
f. Avoid lifting with excessive side load on the jack.
g. Spin the locknut down to the tripod head, as plunger is extending.
h. Keep the release valve closed at all times.
7. To lower the load:
a. Operate the air valve or electric motor or hand pump to relieve pressure on the locknut.
b. Spin the locknut out of the way.
c. Slowly open the release valve located on the panel to lower the load. The speed of lowering is
controlled by the amount the release valve is opened.
d. Close release valve after the plunger is fully retracted.
e. Lower the extension screw by turning clockwise.
f. Fully retract the adjustable footpads (if so equipped).
g. Fully extend hydraulic casters (if so equipped).
h. Cover the jack when not in use to prevent entrance of contaminants and water into the cylinder.
SERVICING:
Servicing the jack consists primarily of the following:
1. When in use, the jack and hydraulic caster (if so equipped) reservoirs should be kept at the proper
level with hydraulic fluid MIL-H-5606 or approved equivalent. Always check fluid levels with jack and
hydraulic caster plungers fully retracted.
2. When in use, the nitrogen precharge in the hydraulic caster shock absorbers (if so equipped) should
be maintained at 275 psig (19.3 kg/sq cm).
3. Grease the swivel casters.
4. Lubricate hand pump pivot pins.
5. Fill pump lubricator with SAE #10 oil.
6. If the jack has been put into storage or has not been used, the plunger must be fully extended and
retracted every 90 days to exercise the seals. A portion of the lift should be operated by the air pump
(if so equipped) and a portion by the hand pump. Also, the hydraulic caster plungers must be fully
extended and retracted by operating the hydraulic caster hand pumps and release valves.
DISASSEMBLY INSPECTION:
CAUTION: THE JACK THERMAL RELIEF VALVE AND SYSTEM RELIEF VALVE,
LOCATED IN THE JACK VALVE BLOCK ASSEMBLY, SHOULD NOT
BE REMOVED UNLESS ABSOLUTELY NECESSARY. THE JACK
THERMAL RELIEF VALVE IS SET TO BY-PASS HYDRAULIC FLUID
BACK TO THE RESERVOIR AT 20-25% ABOVE THE RATED
CAPACITY OF 100 TONS. THE JACK SYSTEM RELIEF VALVE IS SET
TO BY-PASS HYDRAULIC FLUID BACK TO THE RESERVOIR AT 5-
10% ABOVE THE RATED CAPACITY OF 100 TONS. IF ADJUSTMENT
IS REQUIRED, SEE PROCEDURE UNDER TESTING (SEE SHEET 5).
CAUTION: THE HYDRAULIC CASTER RELIEF VALVES (IF SO EQUIPPED),
Property of American Airlines
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