Jim:
Don't think OY was based in Chama. It was there for a while, but an item I found indicated it went to the shop in the summer of 41. I can only assume it must have been damaged and they moved it from Chama to the shop in Alamosa that summer. Don't know why they didn't put it back into service until later, but the snow was not too bad in 42 on Cumbres. 43 was bad again...
February 4, 1943, Thursday
Snow Drifts Six to Twelve Feet Cleared By Rotary on Cumbres
A narrow gauge rotary snow plow opened Cumbres Pass to railroad traffic Thursday afternoon and all trains are now operating over the pass after a one day cancellation of schedule. The rotary crew which left Alamosa at 1:15 a.m. Thursday encountered drifts from six to twelve feet in depth in the vicinity southwest of Antonito.
While the drifts were hard packed, the rotary did not experience quite as hard a time as it did a week ago Monday, according to L.S. Lively, acting Dispatcher for the Rio Grande on the Alamosa line.