Hawk Industries Hawkjaw Jr. Manual 65K-ALS Serial Numbers 4 to 9 - Manual (Page 73)

Trouble Shooting
Symptom Remedy
Push in the Raise button or the
Lower button, and nothing
happens. (cont.)
A loud hissing sound comes
from the Grip button.
Push in a Grip button, and
nothing happens.
Lower button air valve. See Drawings, p. 110, 116.
l
Check that air is reaching the Raise/Lower
hydraulic valve. Make sure the hydraulic power
unit is shut down. Pull out all Grip buttons. The
Raise green air hose connects to Port A on the
Raise/Lower hydraulic valve V4. Disconnect
the Raise button air hose from the Raise/Lower
hydraulic valve V4. To disconnect the air hose, push
the hose and collet ring into the valve pilot port.
While holding down the collet ring, pull out the Raise
green air hose. Place your hand over the discon-
nected Raise green air hose, and push in the Raise
air button. A steady blast of air should come out of
the hose. If air comes out of the hose, replace the
Raise/Lower hydraulic valve. See Drawings, p. 106.
If no air comes out of the hose, the air hoses are
improperly connected within the Left control panel.
See
Drawings, p. 110. Repeat for the
Lower button. The black Lower air hose connects
to Port B on the Raise/Lower hydraulic valve V4.
l
Properly connect the Grip air hoses within the Left
control handle. See Drawings, p. 110.
l
Check to make sure the hydraulic power unit is
producing 2600 psi at 20-35 gpm..
l
Check that the HawkJaw is getting at least 100 psi
air.
l
Check that the pump pressure compensator
setting is at 2600 psi.
l
Check that the hydraulic filter element is not
completely full of contaminants. If the red indicator
button on the hydraulic filter body pops up, change
the filter element. See Filter Maintenance, p. 35.
l
Check that no hissing sound comes from the Grip
button. An air hose is broken or disconnected if
there is a hissing sound. Locate the leak, and
replace the hose. See Drawings, p. 110.
Raise Button
Lower Button
Grip Button
Trouble
Shooting
Troubleshooting 73
Continued on next page.