Cummins 5.9L B / 8.3L C Injector Nozzle Washer, 7mm | 3906659 | FP Diesel

New aftermarket FP Diesel injector nozzle sealing washer, replacing Cummins 3906659. It seals the injector nozzle to the cylinder head at the bottom of the injector bore on Cummins B-series 5.9L and C-series 8.3L engines with 7mm injector nozzles.

Specifications:

• Replaces: Cummins 3906659
• Brand: FP Diesel
• Condition: New Aftermarket
• Component type: Injector nozzle sealing washer (nozzle tip gasket)
• Nozzle size: 7mm
• Inside diameter: .287 in
• Outside diameter: .587 in
• Engine: Cummins B-series 5.9L, C-series 8.3L
• Quantity: 1 washer

Compatibility / Fitment:

Fits Cummins B-series 5.9L and C-series 8.3L engines with 7mm injector nozzles.

Two hard fitment gates apply:

7mm nozzle only. The .287 in bore is sized for a 7mm nozzle body. Injectors with a 9mm nozzle need a different washer.

Standard thickness. This is the standard sealing washer. Some performance injectors for 12-valve engines are set up with thinner washers to change nozzle height. If yours were, use the washer your injector supplier specifies.

Installation: Remove the old washer completely. It can stay stuck at the bottom of the bore, and two stacked washers change nozzle height. Clean the seating surface in the bore, fit a new washer every time an injector goes in, and torque the injector to Cummins specification without over-tightening.

Quantity: one per injector, so six for a 6-cylinder engine.

Other versions available: Interstate-McBee, PAI and Dipaco versions of this washer.

Common interchanges: Cummins 3920174, PAI 042092, Interstate-McBee M-3906659

Conclusion:

An FP Diesel replacement for the Cummins 7mm injector nozzle sealing washer on B-series 5.9L and C-series 8.3L engines. Confirm a 7mm nozzle before ordering, and plan on one washer per injector.