- Track-Type Tractor:
- D7E (S/N: MDB1-UP; TJA1-UP; SCG1-UP; TAN1-UP)
Description of Change: The check valve design has been changed from a plunger type to a ball type. The new design is less susceptible to check valve sticking that may result in overheating of components in the separate circuit when the valve at the separate circuit pump location is stuck open. The new 393-1804 Valve As replaces the 311-4612 Check Valve As located at the separate circuit pump vent line. The 311-4612 Check Valve Assemblies at the other locations in the separate circuit vent lines have been eliminated.
Adaptable To: The new 393-1804 Valve As replaces the former 311-4612 Check Valve As located in the separate circuit pump vent line.
The 311-4612 Check Valve As at other locations in the separate circuit venting system has been eliminated.
New 393-1804 Valve As is adaptable to machines and effective in production with machines that are listed in Table 1.
| Sales Model | Adaptable to Machines |
| D7E | S/N:MDB1-UP |
| S/N:TAN1-UP | |
| S/N:SCG1-UP | |
| S/N:TAJ1-UP |
Rework Procedure
Installation of New 393-1804 Valve As at the Separate Circuit Pump Location (MDB-Up, SCG-Up, TAN1-Up, TJA1-Up)
| Required Parts List | |||
|---|---|---|---|
| Item | Quantity | New Part Number | Description |
| 1 | 1 | 393-1804 | Valve As |
| 2 | 1 | 6V-8398 | O-Ring Seal |
| 3 | 1 | 3K-0360 | O-Ring Seal |
- Remove 311-4612 Check Valve As from the separate circuit pump vent line location.
- Install new valve assembly (1) using O-ring seal (2) and O-ring seal (3) to the separate circuit pump vent line at location shown in Illustration 1.
 | |
| Illustration 1 | g03746082 |
(A) Separate circuit pump vent line | |
Removal of Existing 311-4612 Check Valve As and J-Loop in the Separate Circuit Vent Lines (MDB1-Up, SCG1-Up, TAN1-Up, TJA1-Up)
| Required Parts List | |||
|---|---|---|---|
| Item | Quantity | New Part Number | Description |
| 4 | 1 | 9S-4185 | O-Ring Plug |
| 5 | 1 | 3K-0360 | O-Ring Seal |
| 6 | 1 | 6V-8245 (1) | Elbow |
| 7 | 1 | 6V-9027 | O-Ring Seal |
| ( 1 ) | For MDB and SCG this elbow was removed in the procedure "Removal of 311-4612 Check Valve As at the Generator Vent Line ( MDB, SCG)" |
- Remove J-loop hose (N), hose clamps, and hose clipping hardware (F). Discard all parts.
 | |
| Illustration 2 | g03746085 |
Right-hand side of the machine | |
- Remove connector (M), adapter (L), connector (K), and check valve (H). Discard all parts.
- Remove adapter (G) from tee assembly (E) in the separate circuit return line (J). Discard adapter (G) .
- Install 9S-4185 O-Ring Plug (4) in place of adapter (G) with 3K-0360 O-Ring Seal (5) in the separate circuit return line (J) .
- Temporarily disconnect vent hose (B) .
 | |
| Illustration 3 | g03746111 |
View of area D (Shown in illustration 2) | |
- Remove tee (C) from the bulkhead port. Discard the part.
- Install elbow (6) using O-ring seal (7) to the bulkhead port. Refer to Illustration 3.
- Install vent hose (B) that was removed in Step 5 in the same location.
Removal of 311-4612 Check Valve As at the Generator Vent Line (MDB1-Up, SCG1-Up)
| Required Parts List | |||
|---|---|---|---|
| Item | Quantity | New Part Number | Description |
| 8 | 1 | 9S-8005 | O-Ring Plug |
| 9 | 1 | 9S-4182 | Plug |
| 10 | 1 | 3J-7354 | O-Ring Seal |
| 11 | 1 | 3K-0360 | O-Ring Seal |
- Remove vent hose (P), and hose clamps, tube (R), elbow (S), adapter (T), and connector (U) from the generator (V). Save elbow (S) for use in "Removal of Existing 311-4612 Check Valve As and J-Loop in the Separate Circuit Vent Lines". Discard the other parts. Refer to Illustration 4.
 | |
| Illustration 4 | g03746114 |
Right-hand side of engine | |
- Remove the existing check valve (W) from the port on generator. Discard the part.
 | |
| Illustration 5 | g03746124 |
- Install O-ring plug (8) with O-ring seal (11) to the port on the generator as shown in illustration 6. Tighten O-ring plug (8) to 55 ± 10 N·m (41 ± 7 lb ft).
 | |
| Illustration 6 | g03746702 |
- Remove vent hose (X) and associated hose clamps and attached hardware. Refer to Illustration 7.
 | |
| Illustration 7 | g03746125 |
Right-hand side of engine | |
- Remove elbow (Z) from the generator vent line port to shunt tank (Y) as shown in Illustration 8. Discard elbow.
 | |
| Illustration 8 | g03746131 |
Right-hand side of engine compartment | |
- Install Plug (9) to the generator vent line port with O-ring seal (10) to shunt tank.