The first two were rated by the manufacturer for 72 bhp (54 kW) at 4200 RPM and 96 lb⋅ft (130 N⋅m) of torque at 2800 RPM; the increase in displacement reduced emissions in order to meet US automobile emissions requirements.

The camshafts and fuel injection pump are driven by a duplex chain from the crankshaft.

A separate single row chain drives the oil pump from the crankshaft.

The OM-601's injection pump is a mechanical fuel injection unit with a 5,150 RPM (+ or - 50 RPM) mechanical governor, automatic altitude compensation, and a 'load sensing' automatic idle speed control.

Use of the block heater was recommended in climates where it drops below 10 °F (−12 °C) for long periods.