Toro Groundsmaster
4000?D Service Manual page 145

PRELIMINARY – For Toro Distributor and Toro Company use only.
Disassembly (Fig. 83)
1. Pump oil out of cylinder into a drain pan by SLOWLY
moving rod and piston in and out of cylinder bore. Plug
ports and clean outside of cylinder.
IMPORTANT: To prevent damage when clamping
cylinder in a vise, clamp only on pivotal ends. Use
of a vise with soft jaws is recommended.
2. Mount cylinder in a vise so rod end of cylinder is tilted
up slightly. Do not close vise so firmly that cylinder tube
could become distorted.
3. Loosen head from tube:
A. Use a spanner wrench to rotate head clockwise
until the edge of the retaining ring appears in the tube
opening.
B. Insert a screwdriver under the beveled edge of
the retaining ring to start the retaining ring through
the opening.
C. Rotate the head counter−clockwise to remove re-
taining ring from tube and head.
4. Grasp end of piston rod and use a twisting and pull-
ing motion to carefully extract piston, piston rod and
head from cylinder tube.
IMPORTANT: Do not clamp vise jaws against piston
rod surface; the piston rod will become damaged.
5. Securely mount piston, piston rod and head into vise
and remove piston. Remove head from rod.
6. Remove and discard all seals and O−rings from
head and piston.
Groundsmaster 4000−D
7. Wash parts in clean solvent. Dry parts with com-
pressed air. Do not wipe parts dry with paper towels or
cloth. Lint in a hydraulic system will cause damage.
8. Carefully inspect internal surface of barrel for dam-
age (deep scratches, out−of−round, etc.). Replace en-
tire cylinder if barrel is damaged. Inspect rod and piston
for evidence of excessive scoring, pitting or wear. Re-
place any damaged parts.
Assembly (Fig. 83)
1. Use a complete repair kit when rebuilding the cylin-
der. Put a coating of clean hydraulic oil on all new seals
and O−rings.
2. Install new O−rings and seals to the piston and head.
3. Lubricate shaft with clean hydraulic oil. Slide head
onto shaft. Install and tighten head. Torque head from 45
to 55 ft−lb (62 to 74 N−m).
4. Put a coating of clean hydraulic oil on all cylinder
parts to ease assembly.
5. Slide rod assembly into cylinder tube.
6. Mount steering cylinder in a vise with soft jaws. Se-
cure head in barrel:
A. Align retaining ring hole in the head with the ac-
cess slot in the tube.
B. Insert the retaining ring hook into the hole and ro-
tate head clockwise until the retaining ring is com-
pletely pulled into the tube and the ring ends are
covered.
C. Apply silicone sealer to tube access slot.
Page 4 − 111 Hydraulic System