Described and illustrated is the D348, a diesel engine in the 1000 horsepower class, which features turbocharging, aftercooling, overhead camshafts, and four valves per cylinder. Easy valve adjustment, unit removal and installation, and simple timing procedures exemplify design emphasis on serviceability. All components are either permanently lubricated or are lubricated by the engine lubricating oil system to minimize maintenance requirements. The basic vehicular engine with a weight-to-power ratio of 6.6 lb/hp and a specific output of 0.55 hp/cu in. displacement is readily adaptable into industrial, marine, and electric set configurations