- Wheel Tractor-Scraper:
- 621K (S/N: WTA1-UP; WTE1-UP)
- 623K (S/N: WTB1-UP)
- 627K (S/N: WTC1-UP)
Description of Change: An improved routing for the nitrogen oxide sensor assembly is now used on the machines listed above. The improved nitrogen oxide sensor assemblies routing will provide better clearance to hood covering over exhaust tube. The new routing will provide extended service life.
Adaptable To: The new 452-6176 Tube As is part of the 378-2942 Dust Ejector Gp. The new 154-6626 Bracket As is part of the 374-8770 Engine Wiring Gp .
The new 461-7336 Tube As is part of the 440-2172 Dust Ejector Gp. The new 192-5017 Bracket As is part of the 374-8675 Engine Wiring Gp .
New parts are adaptable to machines and effective in production with machines that are listed in Table 1.
| Sales Model | Adaptable to Machines | Effective in production with Machines |
| 627K | S/N:WTC1-163 | S/N:WTC164-UP |
| 623K | S/N:WTB1-141 | S/N:WTB142-UP |
| 621K | S/N:WTA1-111 | S/N:WTA112-UP |
| S/N:WTE1-109 | S/N:WTE110-UP |
Rework Procedure for 621K, 623K, and 627K Tractors
| Required Parts List | |||
|---|---|---|---|
| Item | Quantity | New Part Number | Description |
| 1 | 1 | 452-6176 | Tube As |
| 2 | 1 | 154-6626 | Bracket As |
| 3 | 2 | 8T-4137 | Bolt |
| 4 | 2 | 326-4516 | Cable Tie |
- Install new tube assembly (1) in the 378-2942 Dust Ejector Gp .
 | |
| Illustration 1 | g03740411 |
- Install 359-9172 Nitrogen Oxide Sensor As (A) to new tube assembly (1). Tighten nitrogen oxide sensor as (A) to a torque of 50 ± 10 N·m (37 ± 7 lb ft). Refer to Illustration 1.
Note: Maintain a distance of 170 ± 5 mm (6.7 ± 0.2 inch) between outlet nitrogen oxide sensor assembly and first clip point.
- Remove 9L-1566 Support, two bolts, two 8T-4121 Hard Washers, and two nuts from 374-8770 Engine Wiring Gp. Save hard washers and discard all other parts.
- Install new bracket assembly (2) using two bolts (3) and two 8T-4121 Hard Washers that were saved in Step 4.
 | |
| Illustration 2 | g03740424 |
- Orient ladder clip (C) in upward direction as shown in Illustration 2.
- Secure lead (B) of sensor cable assembly to ladder clip (C) using cable tie (4). Refer to Illustration 2.
Note: Maintain a distance of 185 ± 5 mm (7.3 ± 0.2 inch) between inlet nitrogen oxide sensor assembly and first ladder clip point.
Rework Procedure for 627K Scraper
| Required Parts List | |||
|---|---|---|---|
| Item | Quantity | New Part Number | Description |
| 1 | 1 | 461-7336 | Tube As |
| 2 | 1 | 192-5017 | Bracket As |
| 3 | 2 | 326-4516 | Cable Tie |
- Remove 379-5639 Tube As (A) from 440-2172 Dust Ejector Gp. Discard tube assembly.
 | |
| Illustration 3 | g03740493 |
- Remove 124-3019 Bracket As (B) from 374-8675 Engine Wiring Gp. Discard bracket assembly and retain the clip and hardware for reuse.
- Install new tube assembly (1) in the 440-2172 Dust Ejector Gp .
 | |
| Illustration 4 | g03740500 |
- Install 359-9172 Nitrogen Oxide Sensor As (C) to new tube assembly (1). Refer to Illustration 4.
- Torque 359-9172 Nitrogen Oxide Sensor As (C) to 50 ± 10 N·m (37 ± 7 lb ft).
- Install new bracket assembly (2) in 374-8675 Engine Wiring Gp. Reuse clip and hardware that was saved in Step 2. Refer to Illustration 4.
- Secure 359-9172 Nitrogen Oxide Sensor As (C) using ladder clip (D) and cable tie (3) as shown in Illustration 4.
Note: Maintain a distance of 127 ± 3 mm (5.0 ± 0.1 inch) between outlet nitrogen oxide sensor assembly and first ladder clip point. Do not pull wire tightly at sensor end.