The electric fan is a poor substitute for an engine-driven one. Pulling hard with a heavy load at high RPM in the lower gears when the fan is needed the most is when the constant-flow electric is likely to come up short. I'd suggest replacing it with a proper mechanical fan.
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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