Toro Groundsmaster 7210 Service Manual page 192

Disassembling the Polar Trac Lift Cylinder (continued)
Inspecting the Polar Trac Lift Cylinder
Assembling the Polar Trac Lift Cylinder
Hydraulic System: Service and Repairs
When you clamp the lift cylinder in a vise, clamp the clevis end of
the cylinder head only to prevent damage.
2. Mount the lift cylinder correctly in a vise by clamping the clevis end of the
cylinder head. Use a vise equipped with soft jaws.
3. Use a spanner wrench, rotate the head clockwise until the edge of the
retaining ring appears in the cylinder head opening. Insert a screwdriver
under the beveled edge of the retaining ring to start the retaining ring through
the opening. Rotate the head counterclockwise to remove the retaining ring
from the cylinder head (item 2 in
4. Remove the plugs from the ports. Carefully twist and pull the shaft and
remove the shaft with head and piston.
Clamping the vise jaws against the rod surface could damage the
rod. When securing the rod in a vise, clamp the rod clevis only.
5. Mount the rod correctly in a vise by clamping on the clevis of the rod. Remove
the locknut and piston from the rod. Carefully slide the head off the shaft.
6. Remove the cap seal and O-ring from the piston. If necessary, remove the
wear ring from the piston.
Note: Do not scratch or damage the piston.
7. Remove the O-ring, back-up ring, wiper, and seal from the head.
Note: Do not scratch or damage the head.
Use eye protection such as goggles when using compressed air.
1. Wash all the lift cylinder components in clean solvent and dry them with
compressed air.
2. Inspect the internal surface of the cylinder head for deep scratches,
out-of-roundness, and bending.
Note: Replace the cylinder head if it is worn or damaged.
3. Inspect the head, shaft, and piston for excessive pitting, scoring, and wear.
Note: Replace the parts if they are worn or damaged.
1. Ensure that all the lift cylinder parts are clean before assembly.
2. Put a coating of clean hydraulic fluid on new O-rings, back-up ring, and other
seals, and do the following steps:
A. Carefully install the cap seal and O-ring to the piston. If removed, install
the wear ring on the piston.
IMPORTANT
Figure 131) and head.
IMPORTANT
CAUTION
Page 4–132 Groundsmaster 7210
16222SL Rev C