- Truck Engines:
- 3176B (S/N: 3NL; 7LG; 9CK; 9WK)
- 3176C (S/N: 2AW)
- C-10 (S/N: 2PN; 3CS; 8YS; BEW)
- C-12 (S/N: 1YN; 2KS; 9NS; BFH)
Description of Change: A new valve bridge assembly is now in production for the above truck engines. The new valve bridge assembly (Illustration 1) is symmetrical and the former valve bridge assembly (Illustration 2) was not symmetrical.
The new valve bridge assembly is used on both intake valves and exhaust valves for engines without a compression brake. The new valve bridge assembly is used ONLY on the intake valves of engines with compression brakes.
The former valve bridge assembly was installed with the slot that was facing toward the rocker arm assembly for the intake valves. The new valve bridge assembly may be installed with the slotted end toward the rocker arm assembly or the slotted end away from the rocker arm assembly.
A valve bridge assembly that is reused must have the original orientation of the valve bridge assembly due to the existing wear pattern from the rocker arm assembly. The valve bridge assembly and rocker arm assembly must be kept together because of the wear pattern on the valve bridge assembly.
The valve lash setting for the new valve bridge assembly is the same valve lash setting as the former valve bridge assembly.
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| Illustration 1 | g00769615 |
(1) New Symmetrical 176-4168 Valve Bridge Assembly
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| Illustration 2 | g00769610 |
(2) Former 144-2913 Valve Bridge Assembly
Adaptable To: The improved valve bridge assembly became effective in production on the truck engines with the following serial numbers:
- C-10 (S/N: 3CS17521-UP)
- C-12 (S/N: 2KS57560-UP)
- 3176B (S/N: 3NL1-UP; 7LG1-UP; 9CK1-UP; 9WK1-UP)
- 3176C (S/N: 2AW1-UP)
- C-10 (S/N: 2PN1-UP; 3CS1-UP; 8YS1-UP; BEW1-UP)
- C-12 (S/N: 1YN1-UP; 2KS1-UP; 9NS1-UP; BFH1-UP)