Autoquip FREIGHTLIFT FLH - Manual (Page 84)

84
CYLINDER REMOVAL AND REPACKING
1. Press the “DOWN” button and lower the carriage to the fully down position.
Continue to hold the button for five to ten seconds to relieve all hydraulic pressure
and cable tension.
2.
Cut off the electricity to the power unit (lock out-tag out).
3. Disconnect the hydraulic hose from the power unit and place the loose end of the
hose in the fill hole of the power unit for draining oil.
4.
Remove the cylinder clevis pin at the base of the cylinder and allow the cylinder to
hang from the cable attached to the sheaves.
5.
Remove the cotter pin from the end of the rod that fits into the sheave mounting
block.
6. Hold the cylinder securely and remove the nut from the threaded end of the
cylinder rod inside the sheave mounting block.
7.
Once free from the sheaves, push the piston rod into the cylinder to eject as much
oil as possible into the power unit or another container.
8.
Insert a Spanner wrench and turn the upper bearing assembly clockwise until the
tip of the retainer appears in the slot. Place a small screwdriver under the retainer
and turn it until the retainer is completely removed.
9.
Be sure the hose port is open to allow air into the cylinder. Pull the piston rod out
to remove the upper bearing.
10. After all of the internal components have been removed, use a bright light to
inspect the inner walls of the barrel. Use a cylinder hone to remove any apparent
nicks or scratches. Clean and flush the barrel after honing.
11. Remove the piston head nut from the rod. The thread or cotter pin hole may be
used to prevent rotation of the rod while loosening. Remove the old piston.
12. Inspect the groove for nicks or scratches that could affect the seal or barrel walls;
remove as necessary.
13. Install the new piston seals and rod wiper.
GENERAL MAINTENANCE