BobCat S70 – CYLINDER (TILT) – Disassembly And Assembly

Use the following tools to disassemble and assemble the cylinder:

MEL 1074 – O-ring Seal Hook
MEL 1396 – Seal Installation Tool
MEL 1033 – Rod Seal Installation Tool
Piston Ring Compressor
Spanner Wrench

Hold the hydraulic cylinder over a drain pan and move the rod in and out slowly to remove the fluid from the cylinder.

Put the base end of the cylinder in a vise.

Use a spanner wrench to loosen the head [Figure 20-21- 6].

Remove the head and the rod assembly from the cylinder (Item 1) [Figure 20-21-7].

Put the rod end in a vise.

Remove the nut (Item 1), piston (Item 2), spacer (Item 3) and head (Item 4) [Figure 20-21-7]

Assembly: Tighten the nut (Item 1) [Figure 20-21-7] to 250 ft.-lb. (339 Nโ€ขm) torque.

Remove the seal (Item 1) and O-ring (Item 2) from the piston (Item 3) [Figure 20-21-8].

Remove the thick O-ring (Item 1) and the back-up washer (Item 2) from the groove in the head. Remove the thin O-ring (Item 3) [Figure 20-21-9].

Remove the wiper seal (Item 1),and the rod seal (Item 2) [Figure 20-21-10].

Remove the O-ring (Item 3) [Figure 20-21-10] from the rod seal.

Wash the cylinder parts in solvent and air dry them.

Inspect the cylinder for nicks, scratches or other damage.
Replace any damaged parts.

Always install new O-rings and seals during assembly.

Lubricate all O-rings and seals with hydraulic oil during installation.

Install a new seal on the tool and slowly stretch it until it fits the piston (Item 1) [Figure 20-21-11].

Allow the seal the stretch for 30 seconds before installing it on the piston.

Use a ring compressor to compress the seal to the correct size. Leave the piston in the compressor for about three minutes.

Install the rod seal on the rod seal tool [Figure 20-21-12].

NOTE: During installation the O-ring side of the seal must be toward the inside of the cylinder.

Rotate the handles to collapse the rod seal.

Install the rod seal in the head [Figure 20-21-13].

Install the wiper seal with the wiper toward the outside of the head.

Assemble the cylinder(s) in the reverse order.