David, there is some space in the tender if I seal off the original water tank. I already opened the water fill hatch and have made plugs for the four 3/16" holes in the floor, but I never really intended to have some type of automatic feed system. There is no real room for an axle pump on the loco, but I have given some consideration to an electric feed pump in a trailing car using a R/C airplane fuel tank like this:
Bob, I do not have the fuel tank completed to allow the sump to be automaticly topped up, but it's going to be rather large, it nearly fills the entire coal bunker shown above. The loco took a fair amount of time to get pressure up until I was on the blower, that's when I realized I need new batteries in the fan. I'm planning on doing a full blown shakedown this coming weekend and the grand unveiling the following weekend at Dr. Rivet's Spring Narrow Gauge Meet. I should be able to provide a full description of performance and I might actually be able to get a video on YouTube.