Every oil burner I've been around carries more than enough oil to last through a day's operation. If you start the day with a full bunker of oil, you should be fine. It's always a good idea to check it halfway through the day, to make sure nothing is going wrong.

The only time I ever got close to running out of fuel was during a 2-day railfan event we did with the SLRG 18. We ran to La Veta the first day, and came back the second day. We did a lot of runbys, and burned a lot of fuel. When we got to within a few miles of the summit the second day, the firing valve needed to be opened much further than normal to keep enough fire in the locomotive. When we got to the summit at Fir we had only 300 gallons of oil left. The low fuel level and the fact that the fuel also had to flow up a 3% grade added to the situation. Thankfully, we were done doing runbys, and it was all downhill to Alamosa from there. We got in to Alamosa with about 100 gallons of fuel remaining.