Cranking Motor Requirements

The cranking motor is basically a device for converting electrical power from the batteries to mechanical power for rotating the engine. To obtain satisfactory cold cranking performance, the power available from the cranking system must be equal to or greater than the power required by the engine. Greater cranking system power can be obtained by increasing the battery output and by matching the battery power with a cranking motor of adequate size to carry the higher loads without overstressing or overheating. This paper discusses the specific conditions that must be evaluated for determining the best way to improve cold starting.