Power steering cooler question.
I need to put a cooler on the system over the winter, but some aspects don't make sense to me. The coolers all seem to be in the return line to the pump. Correct me if I'm wrong, but isn't most of the heat generated in the system due to the pressure/bypass in the pump? It seems to me that the fluid in the reservoir just keeps getting hotter as the engine (and therefore the pump) is at high RPMs in the straights, and then when you turn into the corner all this hot fluid is pumped into the rack. The hot fluid exiting the rack then goes through the cooler, gets cooled a touch, and then goes into the reservoir to be heated up again down the next straight. The low pressure location of the cooler only makes sense to me if there is a low volume quiescent flow through the system all the time, allowing the cooler to continually pull heat out of the fluid. It seems the best location for a cooler is in the line between the pump and the rack so that the fluid can be cooled before it gets to the rack (although the line pressure issue gums up the works).
So, help me understand things. My main concern here is protecting the rack from overheated fluid. The pump was uber cheap ($10) and easily replaceable, but the rack is a custom width unit that was a PITA to procure and not cheap.
I'd appreciate some input here to make sure I understand things before I waste a lot of time replumbing the lines.