I have a tan world 1900. I over bought on the gallons per hour return, and by that I mean, misounte can't keep up with the amount of flow it produces. To compensate I put in shut off valves to add a little resistance and slow down the return. My fear is that I may be causing a little more stress on the motor then is necessary. So to the subject, how hot do Extertal pumps get? This is the first time I've ever used an external blog, and I just wanted to make sure that I'm not screwing the pump up.