Southworth APCU Series, Operating And Maintenance Manual

Page: 35 / 46

APCU Owner’s Manual 35
6. At the top end of the rod remove the “keeper” from
the upper cylinder clevis and drive out the upper
clevis pin. Repeat the same procedure to remove
the lower cylinder clevis pin.
7. Push the rod back into the cylinder to drive the
hydraulic fluid out through the hose and into the
container. You may use air pressure at the hydrau-
lic port to do this.
8. Now the cylinder can be removed for repacking or
replacement.
CAUTION!
The cylinder is heavy! Be careful not to
drop it as it comes free!
Repacking a Cylinder
CAUTION!
Repacking the cylinders requires special
training and tools. If you are not familiar
with repacking procedures, this work
should be left to a qualified hydraulic re -
pair shop.
1. Begin by removing the cylinder as described in the
last section.
2. Figure 6 shows the parts inside a cylinder. Secure
the cylinder in a vise so that it cannot turn. Clear
the work area so that you can lay the parts on a
clean surface.
3. At the upper end of the cylinder, remove the snap
ring. Pull the rod to within 3 inches of full exten-
sion. Compress the ring and, at the same time, pull
outward on the rod. This will pull the gland out of
the cylinder.
4. Pull the rod and piston all of the way out of the
cylinder. This assembly is heavy! Be careful not
to drop it as it comes free.
5. Remove the piston from the cylinder rod. (Be
careful to protect the cylinder rod as you do this.
Any burrs on the rod could damage the packing.)
Note the position of the piston ring and remove it.
Remove the leather BU washer and larger O-ring
from the piston. Remove the smaller O-ring which
fits around the cylinder rod.
6. Remove the gland from the cylinder rod by
sliding it off of the end which holds the piston. No-
tice how the wiper ring sits in the gland. Note the
positions of the quad ring and BU washer. Remove
the wiper ring, quad ring and BU washer from the
gland.
Fig. 6 Repacking a Cylinder