raise the ram. Opening the release valve allows
oil to flow from the cylinder to the reservoir,
This section describes, locates, illustrates, and
causing the ram to lower.
furnishes the operator, or crew sufficient infor-
14. RAM LOCK NUT.
mation pertaining to the various controls pro-
vided for proper operation of the tripod hydrau-
The ram lock nut (4, figure 1) is located on
the ram (3) at the top end of the cylinder and
ram assembly (5). It provides a means of secur-
12. AIR VENT ASSEMBLY.
ing the ram in its raised position.
The air vent assembly (1, figure 2) located in
15. RISE INDICATOR.
the top of the reservoir (3) is provided to estab-
lish a zero pressure condition in the reservoir
The rise indicator (1, figure 1) is secure to the
during operation of the pump assembly, permit-
top end of the ram with a collar and wingnut.
ting a free flow of oil. The air vent must be closed
When used in conjunction with the rise indicator
when the jack is not in use to prevent oil leak-
decalcomania on the side of the cylinder, the rise
age and contamination of the oil by dirt and
indicator shows the distances, in inches, the ram
travels when the pump is actuated.
13. RELEASE VALVE.
The release (6, figure 2), located at the lower
The handle (8, figure 2), which is inserted in
right side of the pump body (4) controls the
the socket (7), is actuated to give the pump
return flow of oil from the cylinder and ram as-
piston the necessary reciprocating action required
to force oil into the cylinder and raise the ram.
sembly. The release valve must be closed to
Section III. OPERATION UNDER USUAL CONDITIONS
d. Maximum Closed Height. For this height
both sets of three leg extensions (9) are used.
Instructions in this section are published for the
The no. 2 braces (8) are swung down from their
use of personnel responsible for the operation
previous position and attached to the leg exten-
of this equipment, It is essential the operator
sions with the links (10) and to the feet with
know how to perform every operation of which
no. 3 braces (11).
the tripod hydraulic jack is capable.
19. OPERATING DETAILS.
18. SETTING UP INSTRUCTIONS.
a. Positioning. The ground surface under the
a. General. The jack may be assembled in any
jack should be level. If the ground is soft, a board
of three basic closed heights by the use of the
or plank should be placed under each foot.
leg extensions. Figure 1 shows the jack with all
The jack should be placed so a Line drawn
extensions installed. The broken lines indicate
through the center of two of the feet will be
the three possible foot assembly positions.
parallel to the fuselage of the airplane or load to
b. Minimum Closed Height. For this height the
cylinder and ram assembly (5, figure 1), is
mounted on the three legs (6) and the three foot
assemblies (12) are installed directy on the bot-
Do not extend the extension screw more
tom of the legs. Six no. 1 braces (7) are used.
than 12 inches
c. Intermediate Closed Height. Refer to para-
graph 18b, with the addition of one leg exten-
(1) Turn the extension screw (2, figure 1)
out until the socket in the screw contacts the
sions. Six each of the no. 1 braces (7) and no. 2
load to be lifted.
braces (8) are used.