Autoquip FREIGHTLIFT FLT - Manual (Page 63)

63
GENERAL MAINTENANCE
CYLINDER AND/OR SEAL REPLACEMENT
Cylinder Removal
1. While the lift is in the lowered position, remove the cap screw which holds the top
cylinder rod of the double ram assembly to the carriage thrust angle at the top rear
of the carriage.
2. Press the “UP” button and raise the carriage up high enough to place the
maintenance blocks underneath the carriage in all four corners (see “Blocking
Instructions” section).
3. Lower the carriage onto the maintenance blocks and continue to press the “DOWN”
button for an additional ten seconds in order to bleed the pressure off the system.
4. Disconnect the hydraulic hose from the two rams. Drain the oil into a bucket as the
cylinders retract and the oil drains from the hose.
5. If the entire ram assembly is to be replaced and the velocity fuses are to be reused,
disconnect the fuses from the elbow fittings attached to the ram casings. Make note
of the orientation for reinstallation. Refer to Hydraulic Schematic.
6. Unbolt and remove the ram stabilizer arms and wear pads (if applicable) from the
double ram casing. (Stabilizers are most common with high travel units.)
7. The upper rod should have retracted from the carriage thrust angle and the double
ram assembly can now be removed by lifting the bottom rod out of the socket in the
mast base weldment.
Seal Replacement
1. Lay the ram assembly on its side.
2. To access the seal, push the rod down inside the casing past the seals by threading
a bolt into the end of the rod and simply pushing on the bolt. Take all precautions
not to scratch the cylinder rod.
3. Remove the old seal ring and backup ring. Inspect the seal groove for nicks and
scratches that could affect the seal. Remove as necessary.
4. Clean the groove thoroughly and install the new seal and backup. Lubricate the seal
with clean oil or grease.
5. Grasping the bolt in the end of the cylinder rod, pull the rod out of the casing taking
precaution against pinching or tearing the seal ring.