Hey Charlie,
When I was working at the D&S someone told me, I think my boss Steve Jackson, that a K28 boiler holds 2380 gallons when the water comes out of the money tail on the steam dome, with cold water. I remember being impressed that the tender 5000 gallons only would fill up the boiler twice.
During a normal day I figured a K36 used about 15-17,000 gallons and 7-9 tons of coal. The nite watchman would fill the tenders slowly of the night so 5000 gallons, engines took on about 3000 gallons at tank creek, 3000 ga at Hermosa on the way up and 2000 ga at tank creek on the way down. Back in the yard they'd have about 2000 left over when they tied up. Coal could be almost empty and we would load like 5 tons at night, in the morning they would be topped off with maybe 4 tons hopefully with out denting the engine roof or tender with the bucket from the worn out loaders. I think the Case tracker has been rebuilt as often as the K36s.
Day in the life of engine watchman, firemen.
regards Thor