Cummins Gear-Type Engine Oil Pump - Used (Casting 3930338)

Gear-type diesel engine lubricating oil pump with cast-iron body, external gear set, and integral pressure-relief plunger. Casting number 3930338 (cast into the body — casting reference, not a verified orderable OEM service part number) with a C6 foundry mark. Application: consistent with Cummins mid-range diesel engines (B-series style lube pump family) in marine, industrial, and truck service — exact application is not verified. Condition: used take-off, untested. Complete with drive gear, idler gear, and relief plunger; normal gear contact wear, light surface oxidation, and old oil varnish present. No flow, pressure, or run testing has been performed and none is implied. Residual oil will be drained and openings capped before shipping. Buyer must confirm fitment by part number, photos, dimensions, engine model, serial number, and application before purchase. Used marine part sold as-is unless otherwise stated. No returns on electrical, used, special-order, or installed parts.