USE/CARE OF HANDTOOLS & MEASURING TOOLS - OD1621 - LESSON 2/TASK 1
(3) Push-Pull Hydraulic Jacks.
The push-pull hydraulic jacks are
furnished with an assortment of attachments enabling performance of a
variety of pushing, pulling, lifting, pressing, bending, spreading, and
The pump is hand operated.
Turn the control valve
(figure 49 on the previous page) on the side of the pump clockwise, stroke
the hand lever up and down and the ram will extend.
The 6 foot flexible
hydraulic or oil hose allows the ram to operate in any desired position and
from a safe distance. The ram retracts automatically by turning the control
valve counterclockwise. The attachments can be threaded to the end of the
plunger, to the ram body, or into the ram base. Figures 50 through 53 on
the following pages illustrate some standard combinations of the push-pull
hydraulic jack attachments for various operations, including a specially
designed spread ram.
d. Care of Jacks. Coat all surfaces with a thin film of light oil when
not in use. For a long period of storage the jacks should he covered with a
rust preventive compound and stored in a dry place.
with a fill plug and it is necessary to stand the pump on end before
Make certain the ram is in the retracted position when checking
the level of oil and when filling.
e. Precautions. Keep fingers away from all moving parts. When jacking
up vehicles make certain no one is under the vehicle to be raised. Place
blocking or other supports under the vehicle when it is raised to the
desired height to prevent it from dropping if the jack fails. Make certain
hydraulic jacks are filled with oil and that there are no visible oil leaks
Bars and Mattock
Bars are heavy steel tools used to lift and move heavy
objects and to pry where leverage is needed. They are also used to remove
nails and spikes during wrecking operations.
The mattock is used for
digging in hard ground, cutting roots underground, and to loosen clay
formations in which there is little or no rock.
The mattock may also be
used for light prying when no bars are available.