John Deere Cast Heat Exchanger End Cap for 300 Series Engine - Used

John Deere-style cast heat exchanger end cap, tagged for a John Deere 300 Series engine. The casting reads R108727A (casting number as it appears on the part — the corresponding John Deere service number must be verified before ordering). Features an oval 3-bolt mounting flange, machined bore with seal land for the exchanger tube bundle, one threaded port boss, and a short tube nipple. Condition: used, untested take-off. Chipped OEM yellow paint, surface dirt, and light oxidation in the bore; no cracks visible in the photos, but the part has not been pressure tested or crack tested. No seals, gaskets, or hardware included. Ports will be capped and the part drained before shipping. Application not verified — offered on the strength of photos, the cast identifiers, and dimensions. 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.