Usage:
D8N (9TC, 5TJ, 1XJ, 7TK),
D9N (1JD, 6XJ),
D10N (2YD, 3SK),
Track-Type Tractors;
578 (8HB),
589 (31Z) Pipelayers
Description of Change: The fan drive and belt tightener groups with a "Lube For Life" design on the machines are no longer used. The new design, which increases bearing and seal life, uses hydraulic fittings and hoses to establish the need for a scheduled periodic lubrication of the fan drive group and the belt tightener group. The improved design utilizes a different seal.
Adaptable To: The improved 4P-9297 Fan Drive Group and 4P-1705 Belt Tightener Group are effective with the D8N (5TJ1951, 7TK1451) Track-Type Tractors. The improved 4P-1761 Fan Drive Group and 4P-1768 Belt Tightener Group are effective with the D9N (6XJ861) Track-Type Tractor. The improved 4P-1753 Fan Drive Group is effective with the D10N (3SK826) Track-Type Tractor (hydraulic fitting was installed effective with D10N (3SK620-825) Track-Type Tractors. The improved 4P-1759 Fan Belt Tightener is effective with D10N (3SK677) Track-Type Tractor. The improved 4P-3876 Fan Drive Group and 4P-1705 Belt Tightener Group are effective with the 578 (8HB539) Pipelayer. The improved 6I-2403 Fan Drive Group and 4P-1768 Belt Tightener Group are effective the 589 (31Z475) Pipelayer. The improved fan drives and belt tighteners are a direct replacement for the former groups used on the D8N (5TJ375-1950) Track-Type Tractors, D9N (6XJ1-860) Track-Type Tractors, D10N (3SK1-619) Track-Type Tractors; 578 (8HB483-538) Pipelayer, and 589 (31Z474) Pipelayer. The fan drive and belt tightener groups on these machines can be reworked to the "Requiring Periodic Maintenance" design. Use the following procedures to do the rework.
Procedure To Rework Earlier Fan Drive Groups
1. Remove the fan drive from the machine following the detailed instructions in the appropriate Service Manual.
2. Disassemble the fan drive enough to remove the seal from the back of the drive.
3. Clean the bearings and check for smooth operation.
NOTE: Do not spin the bearing with high pressure air.
4. Pack the bearings with 2S-3230 Bearing Lubricant and assemble the bearings and spacer in the hub.
Illustration 1. (1) Seal. (2) Hub. (3) Fan Adapter. (4) Spacer. (5) Bracket Assembly
5. Lubricate the seal lips lightly with 2S-3230 Bearing Lubricant. Install the Appropriate seal (1) and spacer (4) into hub (2) as shown in Illustration 1.
NOTE: The cross section of the seal to ensure correct seal placement in the hub assembly.
6. Reassemble fan drive per appropriate Service Manual.
7. Remove the 8T-6764 Plug and install a 3B-8485 Hydraulic Fitting in the bracket assembly (5).
8. Install the fan group on the engine.
9. Using the newly installed hydraulic fitting, lube the fan drive with 2S-3230 Lubricant until lubricant just begins to be visible at the rear of the newly installed seal (1). Thereafter, lube the fan drive every 250 hours.
Procedure To Rework Earlier Belt Tightener Groups
1. Remove the belt tightener group from the engine by removing the fan belts, uncoupling the spring or shock absorber assembly and the pivot retaining bolt.
2. Remove the pulley assembly (8) from the arm assembly (6).
3. Remove the seal, bearings, and spacer from the pulley assembly (8).
4. Clean the bearings and check for smooth operation.
NOTE: Do not spin the bearings with high pressure air.
5. Pack the bearings with 2S-3230 Bearing Lubricant and assemble the bearings and spacer in pulley (8).
Illustration 2. (6) Arm Assembly. (7) Seal. (8) Pulley Assembly. (9) Plug.
6. Lubricate the seal lips lightly with 2S-3230 Bearing Lubricant. Install the appropriate seal (7) into pulley (8) as shown in illustration 2.
NOTE: The cross section of the seal to ensure correct seal placement in the pulley assembly.
7. Reassemble pulley (8) onto the arm assembly (6).
8. Remove the 8T-6764 Plug from the arm assembly and install a 3B-8485 Hydraulic Fitting.
9. Install the belt tightener on the engine using step 1 in reverse order.
10. Using the newly installed hydraulic fitting, lube the fan drive with 2S-3230 Bearing Lubricant until lubricant just begins to be visible at the rear of the newly installed seal (7). Thereafter, lube the belt tightener every 250 hours.
Possible Remote Lubrication System
A remote lubricating system can be installed, if desired, for the fan drive and belt tightener groups. To install a remote system, route the hydraulic hose(s) from the fan bracket or the belt tightener arm assembly to a remote block similar to the latest production models. Due to the variations that may be encountered, refer to the latest Parts Manuals and the following parts list.
