Look at the blade angle on your fan. It's supposed to PULL air through the radiator as it turns, not push it. A reverse rotation water pump will try to flow coolant the wrong direction if the serpentine belt is mis-routed, also, even if the fan blades happen to be angled correctly. I have an idea the direction of rotation of your fan and/or water pump is the problem.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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