Re: Sumpter Valley #14

I believe that what you are seeing is an added line to feed the hose wrapped around the sand dome.

The term for what you are asking is side check valves vs. top check valves. There is no difference in the injectors themselves. The advantage of top checks is that they deliver the water into the steam space where it drops dispersed into the boiler water. This is easier on the boiler than side checks where the injector water runs down the inside of the boiler barrel, creating a localized cool spot that adds stress to the barrel.

That is a wild smokebox front on that engine.