Understanding this component
In general, an O-ring seals a joint when compressed between mating surfaces. In a fuel-filter unit, this kind of seal can help contain fuel and keep air from entering at a joint.
John Deere Part reference
John Deere 51M7042 is recorded as an O-ring in the primary fuel filter unit of the 6.9 L PowerTech engine catalog. The selected entry provides the catalog context for this sealing component.
Recorded applications
Selected catalog references that list this part. A catalog association does not confirm fitment for every machine or configuration.
Catalog context

John Deere 6.9 L PowerTech engine
Check the signed-in Part Book for available diagrams and the complete catalog breakdown.
| Part number | Description |
|---|---|
| 38***37 | Adapter fitting |
| 38***35 | Fitting |
| 51M7042 | O-ring (current part) |
| AH***95 | Filter |
Selected entries from this catalog unit. Other part numbers are masked. Confirm the full breakdown and your machine configuration before ordering.
Listed in the primary fuel filter catalog unit. Confirm the exact engine configuration and applicable catalog notes before ordering.
View model pageGeneral guidance
In general, an O-ring seals a joint when compressed between mating surfaces. In a fuel-filter unit, this kind of seal can help contain fuel and keep air from entering at a joint.
Match the existing part number 51M7042 and confirm its position in the primary fuel filter unit. Check the exact engine configuration and applicable catalog notes before ordering.