Super Powerful 1 1500w Engine Heater fits Detroit Diesel Series 60 (11.1L 677 CID, 12.7L 775 CID). Intallation Information: Pre-1991 engines – Replaces 1 NPT plug in water pump outlet casting on Right front side of engine. 1991 & Newer replaces 1 pipe plug near top front of oil cooler. NEW Top Quality 1500. This powerhouse heater is a hard to find part….. And worth every penny in a cold climate. Made for us right here in the good’ol USA, NOT China! Includes a new heavy gauge 6′ power cord for 110/120V AC and detailed installation instructions. Replace an old heater… Or install in an engine that never had one. A must for smooth safe engine starting below 30 degrees F. We stand by our products.