The goal of this paper is to present an inductance measurement method, and an electromechanical model of the pinion-engaging mechanism for the starter motors. The pinionengaging mechanism is the system of components (solenoid switch, pinion-engaging lever, and overrunning clutch with drive pinion) that engages the drive pinion of the starter motor with the ring gear of the internal combustion engine. The actuator of the pinion-engaging mechanism consists of two concentric iron core coils. The coils are excited by relatively high currents. The electromechanical model of the pinion-engaging mechanism requires inductance of the solenoid and its derivative depending on the position of the iron core.