portion of the units. The come-a-long is used in
PUSH-PULL HYDRAULIC JACK
maintenance as is the chain hoist; however,
because the ratchet mechanism does not allow for
A push-pull hydraulic jack, commonly called
minimal movements, it is NOT recommended for
a port-a-power, consists of a pump and ram
use in the alignment of parts.
connected by a flexible hose (fig. 3-43). Jacks of
Figure 3-42.--Hand-operated ratchet lever hoist (come-a-long).
Figure 3-43.--Push-pull hydraulic jack (port-a-power).