Due to the antique mechanism of this locomotives, are necessary 4 or 5 hours of heating for their efficient work. But at El Maitén El Maitén workshops the thechnicians hav gotten, using compressed air, to reduce this time to 2½ hours. 
The slowness of the system forces to that, when a train circulates, in both heads of the itinerary stays a locomotive ready for an eventual help. 

The Old Patagonian Express has 11 locomotives at the moment, 6 of those which are in activity: 3 Baldwin (U.S.A.) and 3 Henschell (Germany). - The "Certificate of Boiler" authorizes the operation of the locomotive for five years, starting from then it is made a revision and general repair that it allows him three years more of activity. Compliments the eight years of operation, it disassembles it to him and it repairs integrally in El Maitén workshops. 

The locomotive tender has two compartments: One can contain up to 4.500Kg. of fuel-oil, the other one up to 10.000 liters of water. In all the stations of the journey the water is restocked according to the quantity consumed until the place.