Detroit Diesel 12V-71 Marine Heat Exchanger Tank Housing - Used Core

Application: Detroit Diesel 12V-71 (V71 series) marine engine heat exchanger / expansion tank housing, likely OEM P/N 5117713. Original cast Detroit Diesel logo on top cover, end port flanges and mounting brackets present. Condition: Used core. Exterior has surface rust and paint loss; tube-sheet ends and internal core are heavily corroded with visible perforation — sold as a rebuildable core housing, not a plug-and-play unit. Plan on a new tube bundle, cleaning, and pressure test before service. 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.