I've heard that when your pump is deadheading, the hydraulic fluid stops moving over the heat exchanger in the tank, and the fluid temperature in the pump keeps rising and rising.  Is this true?  Will a 10 minute deadhead hurt the pump, or overheat it, or overheat the hydraulic fluid to the point of damaging its viscosity?

great question. We have never had a problem but then again our pump shuts off after 15 minutes or so because of safety thing in the software. Not sure if that is to prevent overheating or not.

our maintenance guy says that is what the kidney loop pump is for...it keeps the fluid flowing across the heat excahnger so you dont overheat.