- Truck Engines:
- C-10 (S/N: 2PN1-UP; 3CS1-UP; 8YS1-UP)
- C-12 (S/N: 9SM1-UP; 1YN1-UP; 2KS1-UP; 9NS1-UP)
Description of Change: A new oil filter base group is now used on these truck engines. The thermostatically controlled oil cooler bypass valve was replaced by a spring-loaded valve. This change has no effect on the operation of the oil filter base group.
Adaptable To: The new 166-1329 Oil Filter Base Group is a direct replacement for the former 122-0725 Oil Filter Base Group. The former oil filter base group has been canceled. The new 166-1329 Oil Filter Base Group is adaptable to all of the listed engines. The new 166-1329 Oil Filter Base Group became effective with the following serial numbers: C-10 (S/N: 3CS5801; 8YS7368) and C-12 (S/N: 2KS17296)
Identification of the Components of the New 166-1329 Oil Filter Base Group
The new 166-1329 Oil Filter Base Group is not serviced at the group level. Illustration 1 and Table 1 identify the individual components of this group.
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| Illustration 1 | g00673681 |
| Components of the New 166-1329 Oil Filter Base Group | |||
| Item | Qty | Pt. No. | Description |
| 1 | 6 | 9M-1974 | Hard Washer |
| 2 | 1 | 166-1328 | Base |
| 3 | 3 | 6V-4367 | O-Ring Seal |
| 4 | 4 | 6V-3940 | Bolt |
| 5 | 3 | 7C-2891 | Cover |
| 6 | 1 | 7C-3954 | Spring |
| 7 | 1 | 111-2645 | Pump Bypass Valve |
| 8 | 1 | 6V-8359 | Bolt |
| 9 | 1 | 7C-3083 | Relief Valve Spring Seat |
| 10 | 1 | 7C-3082 | Retainer |
| 11 | 1 | 7C-3081 | Spacer |
| 12 | 1 | 1A-2170 | Retainer Spring |
| 13 | 2 | 1P-1367 | Plunger |
| 14 | 2 | 7C-3953 | Spring |
| 15 | 1 | 9S-4185 | O-Ring Plug |
| 16 | 1 | 8L-2786 | O-Ring Seal |
| 17 | 2 | 9X-2097 | Studbolt |
Procedure for Conversion of the Former 122-0725 Oil Filter Base Group
Table 2 lists the new parts for converting the former 122-0725 Oil Filter Base Group to the new 166-1329 Oil Filter Base Group.
| Former Parts | New Parts | ||||
| Qty | Pt. No. | Description | Qty | Pt. No. | Description |
| 1 | 122-0726 | Oil Filter Base | 1 | 166-1328 | Base |
| 1 | 9M-0853 | Relief Valve Plunger | 1 | 1P-1367 | Plunger |
| 2 | 6V-5217 | Bolts | 1 | 9X-2097 | Studbolt |
| 1 | 6V-3940 | Bolt | |||
| 1 | 9Y-3902 | Valve | 1 | 1P-1367 | Plunger |
| 1 | 7C-2891 | Cover | |||
| 1 | 7C-3953 | Spring | |||
Perform the following procedure to convert the former 122-0725 Oil Filter Base Group to the new 166-1329 Oil Filter Base Group .
- Disassemble the former 122-0725 Oil Filter Base Group. Refer to the Disassembly and Assembly, "Engine Oil Filter Base" section.
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| Illustration 2 | g00672559 |
Components of the former 122-0725 Oil Filter Base Group | |
| Components of the Former 122-0725 Oil Filter Base Group | |||
| Item | Qty | Pt. No. | Description |
| 1 | 2 | 6V-5217 | Bolts (1) |
| 2 | 2 | 9M-1974 | Hard Washers (2) |
| 3 | 1 | 122-0726 | Oil Filter Base (1) |
| 4 | 1 | 6V-4367 | O-Ring Seal (2) |
| 5 | 1 | 9Y-3902 | Valve (1) |
| ( 1 ) | These components can be discarded. |
| ( 2 ) | These components will be used in Step 4. |
- Assemble all of the components from the former 122-0725 Oil Filter Base Group into the new 166-1328 Base except for the components that are identified in Illustration 2 and Table 3. Discard the components that are identified in Illustration 2 and Table 3 except for hard washers (2) and O-ring seal (4). Hard washers (2) and O-ring seal (4) will be used in Step 4. Refer to the Disassembly and Assembly, "Engine Oil Filter Base" section.
 | |
| Illustration 3 | g00672572 |
Components of the new 166-1329 Oil Filter Base Group | |
| Components of the New 166-1329 Oil Filter Base Group | |||
| Item | Qty | Pt. No. | Description |
| 2 | 2 | 9M-1974 | Hard Washers (1) |
| 4 | 1 | 6V-4367 | O-Ring Seal (1) |
| 6 | 1 | 9X-2097 | Studbolt |
| 7 | 1 | 6V-3940 | Bolt |
| 8 | 1 | 1P-1367 | Plunger |
| 9 | 1 | 7C-2891 | Cover |
| 10 | 1 | 7C-3953 | Spring |
| ( 1 ) | These components were removed in Step 1. |