Remove and Install Hydraulic Cylinders
1. Thoroughly clean around the hose connections, mark the hoses and ports for identification, then disconnect the hoses (1). Cap or plug all openings.
2. Remove the pin (2) at the rod end clevis (3).
3. Support the cylinder as necessary.
4. Remove the pin (4) at the head end clevis (5).
5. Remove the cylinder from the mounting clevises and move the cylinder away.
NOTE: If removing an outboard rotor lift cylinder, the head end clevis will have to be lowered out of the bracket to remove the cylinder.
6. Move the replacement cylinder into position between the clevises.
7. Install the pin at the head end clevis then the pin at the rod end clevis.
8. Thoroughly clean around the hose ends and the cylinder ports, then connect the hoses to the cylinder ports.
Disassemble Hydraulic Cylinder
When disassembling a hydraulic cylinder use care not to damage the surfaces of the rod, piston or interior of the tube assembly. Do not allow dirt to enter the cylinder before taking the piston out, or the piston rod and tube assembly may be scratched.
1. Clamp the cylinder in a vise to prevent it from turning. Do not clamp the cylinder so tightly that the tube is distorted.
2. Unbolt and remove the head cap (1).
NOTE: On some cylinders a retaining ring must be removed from inside the tube to disassemble the head cap. See special instructions below for removing the retaining ring.
3. To remove a retaining ring:
a. Insert a spanner wrench in one of the holes provided (3). Rotate the head until the beveled edge of the ring (2) appears at the milled opening (4) in the tube.
b. Insert a screwdriver under the beveled edge to start the ring through the opening and continue to rotate the head until the ring is completely removed.
4. Remove the rod (5), piston (6), head (7), and head cap as a unit from the tube.
5. Clamp the rod end in a vise, using care not to damage the rod.
6. Remove the nut (8) from the rod and slide the parts from the end of the rod.
7. Remove all seals (9) and O-rings (10).
8. Thoroughly clean all parts in clean solvent and inspect for scoring, scratches or nicks.
Assemble Hydraulic Cylinder
NOTE: Use all new O-rings and seals. Lubricate all O-rings, seals and parts with clean hydraulic oil before assembling.
1. Install a new wiper seal (11) in the head or head cap.
2. Install a new rod seal in the head cap (12). U-cup seals should have the lips facing away from the wiper seal.
3. Install a new backup ring (if used) and O-ring (10) on the head.
4. Slip the head cap (if used) and head (7) onto the rod (5), using care not to damage the seals.
5. Install the O-rings in the piston and the piston seals on the piston. U-cup seals should have the lips facing toward the ends of the piston.
6. Place the piston (6) on the rod and secure it with the nut.
Do not use sharp or pointed instruments to depress the seals.
7. Slide the piston into the barrel using care not to damage the seals. Seal compressors are available to aid in installing the piston, or thin plastic can be wrapped around the seal and removed as the piston enters the barrel.
8. If a locking ring is used to hold the head, push the head into position and install the locking ring. Position the head cap and secure with the capscrews.
NOTE: On some cylinders a retaining ring must be installed inside the tube to assemble the head cap. See special instructions below for installing the retaining ring.
9. To install a retaining ring:
a. Insert a spanner wrench in the holes (2) provided and rotate the head gland until the retaining ring hole is visible through the milled slot (3) in the tube.
b. Insert the hook on the retaining ring (1) into the hole and rotate the head 1 1/4 turns until the ring is completely pulled into the tube and the ends are covered.
NOTE: In most cases the same retaining ring may be used several times.