Spozer191

Hey guys and gals, I'm working on my buddies sc300 with a hydraulic radiator fan. It spins but not fast and I can stop it with my had, the car runs really hot at idle and over heats in the summer. I have replaced every sensor and am to the point of tearing the entire system out and going electric, he is trying to keep it with the stock system but I'm running out of ideas on what it could be. Any help is appreciated.