725 and 730 Articulated Trucks Machine Systems Caterpillar

Removal Procedure

Start By:

1. Remove the fender.

Show/hide table

Cylinders equipped with lock valves can remain pressurized for very long periods of time, even with the hoses removed. Failure to relieve pressure before removing a lock valve or disassembling a cylinder can result in personal injury or death. Ensure all pressure is relieved before removing a lock valve or disassembling a cylinder.

Show/hide table

Personal injury or death can result from sudden suspension cylinder movement. Sudden movement, up or down, can cause the clearance above your head to change rapidly. Read all warning labels on the suspension cylinders before servicing. Do not check the oil in the suspension cylinder until all the nitrogen pressure has been released. Do not, under any condition, remove valves, cover or plugs from the cylinder unless the rod is fully retracted and all the nitrogen pressure is released. Do not stand under the machine when testing or adjusting the suspension cylinders.

Show/hide table

When the suspension is lowered clearances between the machine frames and suspension components are reduced. Persons on or near the machine could be injured by crushing. Keep all personnel clear of the machine until the suspension has been lowered.

Show/hide table

Personal injury or death can result from improper lifting or blocking. When a hoist or jack is used to lift any part or component, stand clear of the area. Be sure the hoist or jack has the correct capacity to lift a component. Install blocks or stands before performance of any work under a heavy component. Approximate weights of the components are shown. Clean all surfaces where parts are to be installed.

Show/hide table

When you are using hydraulic cylinders and puller studs, always ensure that the rated capacity of the puller stud meets or exceeds the rated capacity of the hydraulic cylinder. If the puller stud does not meet or exceed the rated capacity of the hydraulic cylinder, a sudden failure of the puller stud could occur. The sudden failure of the puller stud could result in personal injury or death.

Note: The following procedure will remove one of the suspension cylinders. Repeat the procedure for the opposite suspension cylinder, if necessary.

1. Lower the front suspension. Refer to Testing and Adjusting, "Suspension Cylinder (Front) - Purge and Charge".

2. Put identification marks on all lines, on all hoses and on all tubes for installation purposes. Plug all lines, all hoses, and all tubes. Plugs help prevent fluid loss and contamination of the oil system.
   Show/hide table

   Illustration 1	g01040627

3. Install Tooling (A) under the front frame. Use the Tooling to raise the front frame. Do not raise the front frame more than 50 mm (2 inch).
   Show/hide table

   Illustration 2	g01041197
   Typical example

4. Disconnect grease hose assembly (1) from washer (2).
   Show/hide table

   Illustration 3	g01040624

5. Remove bolt (3) and the washer. Remove bolt (4), the washers, the nut, and washer (2) from suspension cylinder (5).
   Show/hide table

   Illustration 4	g03103301

   Note: Attach Tooling (C) to the nut side of pin (6).

6. Use Tooling (C) in order to extract pin (6) out of the machine frame and suspension cylinder (5).
   Show/hide table

   Illustration 5	g03103360

7. Install Tooling (B) and a suitable lifting device onto suspension cylinder (5). The weight of suspension cylinder (5) is approximately 70 kg (154 lb). Move suspension cylinder (5) out of the machine frame. Remove seal collar (8) and seals (7).
   Show/hide table

   Illustration 6	g01040628

8. Disconnect grease hose assembly (9) from special washer (11). Remove bolt (10), the washers, the nut, and the special washer from suspension cylinder (5).
   Show/hide table

   Illustration 7	g03103442

   Note: Attach Tooling (C) to the nut side of pin (12).

9. Use Tooling (C) in order to extract pin (12) out of the front axle and the suspension cylinder.
   Show/hide table

   Illustration 8	g01040630

10. Use the suitable lifting device to lift suspension cylinder (5) and remove spacer (13) and seals (14). Remove suspension cylinder (5) from the machine.
    Show/hide table

    Illustration 9	g01040634

11. Place suspension cylinder (5) on a suitable work surface. Use Tooling (D) in order to remove retaining ring (15). Repeat the step on the opposite end of the suspension cylinder.
    Show/hide table

    Illustration 10	g01040632

12. Turn suspension cylinder (5) onto the opposite side and use Tooling (E) in order to remove bearing (16). Repeat the step on the opposite end of the suspension cylinder.

Disassembly Procedure

Show/hide table

Cylinders equipped with lock valves can remain pressurized for very long periods of time, even with the hoses removed. Failure to relieve pressure before removing a lock valve or disassembling a cylinder can result in personal injury or death. Ensure all pressure is relieved before removing a lock valve or disassembling a cylinder.

1. Position Cylinder Assembly in Tooling (F).
   Show/hide table

   Illustration 11	g03325717

2. Remove bolts (1) and bracket (2).
   Show/hide table

   Illustration 12	g03325722

3. Remove valves (3) and bolt (4).
   Show/hide table

   Illustration 13	g03325760

4. Loosen head (5) and remove the rod from the cylinder.
   Show/hide table

   Illustration 14	g03325778

5. Remove retainer (6) and remove piston (7).
   Show/hide table

   Illustration 15	g03325790

6. Remove seal (8) and wear ring (9).
   Show/hide table

   Illustration 16	g03325828

7. Remove balls (10).
   Show/hide table

   Illustration 17	g03325966

8. Remove seal assembly (11) and remove O-ring seal (12). Remove head (5) from the rod.
   Show/hide table

   Illustration 18	g03325971

9. Remove lip seal assembly (13) from head (5).
   Show/hide table

   Illustration 19	g03325989

10. Remove seal assembly (14). Remove seal assembly (15), and remove wear ring (16) from head (5).

Assembly Procedure

Show/hide table

Illustration 20	g03325989

1. Install wear ring (16). Install seal assembly (14), and Install seal assembly (15) into head (5).

   Note: Lightly lubricate seals (14) and (15) with the lubricant being sealed.

   Show/hide table

   Illustration 21	g03326017

2. Apply Tooling (H) to the mounting groove in head (5) for lip seal assembly (13). Install lip seal assembly (13) into head (5).

   Note: Lightly lubricate the sealing surface of lip seal assembly (14) with the lubricant being sealed.

   Show/hide table

   Illustration 22	g03325966

3. Install head (5) onto the rod. Install O-ring seal (12) and install seal (11).

   Note: Lightly lubricate seals (11) and (12) with the lubricant being sealed.

   Show/hide table

   Illustration 23	g03325828

4. Install balls (10).
   Show/hide table

   Illustration 24	g03325790

5. Install wear ring (9) and install seal (8).

   Note: Lightly lubricate seal (8) with the lubricant being sealed.

   Show/hide table

   Illustration 25	g03325778

6. Install piston (7) onto the rod. Apply clean grease to the threads of retainer (6) and install retainer (6). Tighten retainer (6) to a torque of 8000 ± 600 N·m (5900 ± 443 lb ft).
   Show/hide table

   Illustration 26	g03325760

7. Install the rod into the cylinder and tighten head (5) to a torque of 600 ± 130 N·m (443 ± 95 lb ft)
   Show/hide table

   Illustration 27	g03325722

8. Install bolt (4) and install valves (3). Tighten valves (3) to a torque of 14 ± 1 N·m (124 ± 9 lb in). The closure torque for valves (3) is 7 ± 1 N·m (62 ± 9 lb in)
   Show/hide table

   Illustration 28	g03325717

9. Install bracket (2) with bolts (1).

10. Remove the Cylinder Assembly from Tooling (F)

Installation Procedure

1. Install suspension cylinder (5) in the reverse order of removal.
   Show/hide table

   Illustration 29	g03862850

   Note: Ensure the large diameter of tooling (J) is orientated toward the large diameter bore of the mounting lugs on the machine frame or axle. If tooling (J) is orientated towards the small bore it will not be possible to remove Tooling (J) during the installation procedure.

   1. Install seal collar (8) or (13).

   2. Orient seals (7) or (14) so the large diameter is towards the strut.
      Show/hide table

      Illustration 30	g03862889

   3. Install Tooling (K) and (L) flush to the inside surface of the mounting lugs.
      Show/hide table

      Illustration 31	g03862897

   4. Position suspension cylinder (5) and ensure that the lips of the seals do not slip into the bearing bore. The seals of the lips should sit flat on the strut bearing bore face.
      Show/hide table

      Illustration 32	g03862927

   5. Remove Tooling (K). Remove Tooling (L) and reinstall with Tooling (M) so that the pin engages the hole in Tooling (J).
      Show/hide table

      Illustration 33	g03862939

   6. Use Tooling (L) and Tooling (M) to drive Tooling (J) from the suspension cylinder while maintaining alignment of the seals and supporting the suspension cylinder prior to the mounting pin installation. Remove Tooling (M).
      Show/hide table

      Illustration 34	g03862942

   7. Use mounting pin (12) or (6) to drive Tooling (L) from the strut and mounting lugs.