- Engine:
- 3406E (S/N: 6BR1-UP; 9NN1-UP; 9WR1-UP; BEM1-UP)
- 3456 (S/N: 3LW1-UP; BFM1-UP; BGA1-UP)
Description of Change: The valve cover seal and the valve cover fastener have been redesigned for the above engines. The new 172-8027 Seal must only be used with (6) new 173-2390 Fastener Assemblies. The old 149-7377 Seal must only be used with (6) old 152-8112 Valve Cover Fastener Assemblies. Interchanging the old seal with a new fastener assembly or the new seal with an old fastener assembly will create an unsatisfactory joint seal. The old 149-7377 Seal is Cancelled Replaced By the new 172-8027 Seal. If the old seal is damaged, or if the old seal is leaking, the seal must be replaced with a new 172-8027 Seal and (6) new 173-2390 Fastener Assemblies. The old 152-8112 Valve Cover Fastener Assembly is still available for situations when the old 149-7377 Seal is undamaged, but the old 152-8112 Valve Cover Fastener Assemblies must be replaced.
Adaptable To: The new seal and the new fastener are effective with the following engines:
- 3456 (3LW157-Up) Industrial
- 3406E (9NN418-Up) Gen Set
- 3406E (9WR1194-Up) Marine
Note: The physical differences between the seals and the fastener assemblies are evident by looking at the following illustrations.
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| Illustration 1 | g00765613 |
(1) New Seal (2) New Fastener (3) Cross sectional view of the new seal | |
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| Illustration 2 | g00765614 |
New Fastener (1) Part number (2) Height of the grommet | |
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| Illustration 3 | g00765833 |
(1) Cover (2) Old Seal (3) Old Fastener (4) Cross sectional view of the old seal | |
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| Illustration 4 | g00765615 |
Old Fastener (1) No part number (2) Height of the grommet | |