The ALCO Century 628 was a six-axle, 2,750 horsepower (2.5 MW) diesel locomotive. 186 were built between December 1963 and December 1968. Cataloged as part of ALCO's 'Century' line of locomotives, the C628 was intended to replace the earlier RSD-15 model.
#330 is the sole remaining Century Series locomotive still in service on the Washington Northern. These days it finds itself resting on the shop tracks in Port Andrews in "standby mode" until a power shortage or emergency calls it to service. It will also occasionally be put into work train service.