- Wheel Tractor-Scraper:
- 631E Series II (S/N: 1AB1446-2111; 1BB1540-1805, 91361-91361 and 99641-99641; 1NB565-1499)
- 631E (S/N: 1AB527-1445; 1BB465-1539; 6PC358-568; 4LD199-1319)
- 631G (S/N: AWK1-UP; CLR1-UP)
- 633E Series II (S/N: 1EB290-340 and 1444-1444; 2PS290-319)
- 637E (S/N: 1FB317-531, 1001 and 75001-75004; 1HB86-690; 1LB467-774, 75470-75470 and 99494-99494; 7CB63-179)
- 637E Series II (S/N: 1FB532-841, 1001 and 75001-75004; 1HB691-980, 1100 and 75002-75003; 7CB180-206)
- 637G (S/N: CEH1-UP; AXT1-UP)
- 651E (S/N: 5XR188-402; 88Z78-300)
- 657E (S/N: 6MB53-UP; 6PR99-UP; 7KR199-UP; 86Z88-UP; 87Z176-UP)
Description of Change: New exhaust tubes and heat shields are now in production for the above 3408E Machine Engines. The new one-piece exhaust tubes replace the former two-piece exhaust tubes. The new exhaust tubes include the following improvements: a redesigned flange, flexible bellows and improved parent material. The new heat shields provide protection to the flexible bellows. These new changes improved the strength and service life of the tubes.
Adaptable To: Refer to the following tables and illustrations for a list of the new part numbers. Each new exhaust tube replaces the following parts: the upper exhaust tube, the lower exhaust tube, the exhaust seal, the exhaust seal ring and a clamp. The new heat shields must be used with the new exhaust tubes.
Note: For the 631E, 633E, 637E Wheel Tractor Scrapers that are powered by 3408 engines, the new exhaust tubes and the new heat shields are part of 176-6619 Air Lines Gp .
Note: The new exhaust tubes and the new heat shields can also be used in 131-3269 Air Lines Gp and 130-8918 Air Lines Gp which are used on 651E and 657E Wheel Tractor-Scrapers.
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| Illustration 1 | g01100974 |
(A) 121-5459 Exhaust Tube As (B) 121-5461 Exhaust Tube As (C) 8N-0878 Clamp (D) 1W-0481 Exhaust Seal Ring (E) 106-9408 Exhaust Seal (F) 121-5455 Exhaust Tube As (G) 121-5457 Exhaust Tube As | |
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| Illustration 2 | g01100976 |
| If any of these parts fail | Replace with all of the following parts | ||
| 121-5459 Exhaust Tube As 121-5461 Exhaust Tube As 8N-0878 Clamp 1W-0481 Exhaust Seal Ring 106-9408 Exhaust Seal |
Item | Qty | Part |
| 1 | 1 | 226-0143 Tube As | |
| 2 | 1 | 226-3861 Heat Shield As | |
| 3 | 3 | 6V-3582 Hose Clamp | |
| If any of these parts fail | Replace with all of the following parts | ||
| 121-5455 Exhaust Tube As 121-5457 Exhaust Tube As 8N-0878 Clamp 1W-0481 Exhaust Seal Ring 106-9408 Exhaust Seal |
Item | Qty | Part |
| 4 | 1 | 226-0144 Tube As | |
| 5 | 1 | 226-3862 Heat Shield As | |
| 3 | 3 | 6V-3582 Hose Clamp | |