The K-36s were used primarily as freight locomotives out of Alamosa to
Durango and to
Farmington, New Mexico, as well as out of Salida to Gunnison (over
Marshall Pass) until 1955 and to Monarch on the
Monarch Branch until 1956. They were built with special valves to allow brake control between locomotives while
double-heading and were commonly found between
Alamosa, Colorado, and
Chama, New Mexico. They were heavily used during the pipe boom in Farmington and hauled long freight trains between Alamosa and Farmington. In 1937, three K-36s, Nos. 482, 483 and 489, were equipped with steam heat and signal lines to haul passenger trains like the
Shavano and the
San Juan Express. Eventually, in 1945, Nos. 484, 485 and 488 were also equipped, too. As of 2023, eight of these locomotives still operate regularly. Nos. 483, 484, 487, 488 and 489 are owned by the
Cumbres and Toltec Scenic Railroad (C&TSRR) and Nos. 480, 481, 482 and 486 are owned by the
Durango and Silverton Narrow Gauge Railroad (D&SNG). However, No. 483 is stored out of service at
Chama undergoing a full cosmetic restoration by the Friends of the C&TSRR as of 2023. These locomotives are popular subjects for
model railroaders and high-quality models in
HOn3 and
On3 scales have been produced by several manufacturers, as well as several hand-built
live steam larger scale models. A notable example is a 1/3 scale,
ridable miniature railway model of number 489, in use on the gauge
Audley End Railway in Essex, England.
Conversion to oil-burning In late 2019, No. 489 temporarily went out of service for a new smokebox installation during its
Federal Railroad Administration (FRA) mandated 1,472-day boiler inspection. However, No. 489's return to service was delayed due to
COVID-19. On December 15, 2020, the C&TSRR announced that in addition to the 1,472-day boiler inspection and rebuild, No. 489 will also be converted from coal-burning to oil-burning. Upon returning to service in June 2021, No. 489 was the first locomotive on the C&TSRR to be converted to oil-burning. On August 3, 2022, the C&TSRR announced that parts have been ordered for a second K-36, No. 487, to be converted from coal-burning to oil-burning over the winter of 2022 to 2023; it was eventually returned to service in 2024. Nos. 484 and 488 are the remaining coal-burning K-36s on the C&TSRR's roster. On the D&SNG, Nos. 480 and 482 have also both been converted to oil-burning, with No. 480 re-entering service in June 2021 and No. 482 re-entering service on December 16, 2021. In August 2022, No. 486's tender was also converted to oil-burning for temporary use behind No. 480. The D&SNG will also eventually overhaul and convert No. 486 from coal-burning to oil-burning as well, as its tender was converted to oil-burning setup for temporary use behind No. 480. As of June 2023, No. 481 is the last operational coal-burning locomotive left on the D&SNG's current roster, as the others were converted or are being converted to oil-burning locomotives. ==Roster==