A solenoid actuator includes a housing, a bobbin assembly, a coil, and a washer. The bobbin assembly is disposed at least partially within the housing, and includes a return pole and an armature. The return pole is fixedly coupled to the housing, and the armature is axially movable within the housing. The coil is disposed within the housing and is wound around at least a portion of the bobbin assembly. The washer is disposed between the coil and a portion of the bobbin assembly and surrounds a portion of the return pole. The washer is formed of an electrical insulator material.