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Old 10-05-2019
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badandy badandy is online now
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Join Date: Dec 2016
Location: delavan
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Cold oil = the fan spins more when "off". When you speed up the engine, even though the fan is "off", there's enough cold thick oil to spin the fan even faster, like a lot faster. When the oil warms up, which takes quite a bit of driving at 30 degrees, it will settle down.

The on/off valve for the fan is a bypass, and it just can't bypass as much ice cold thick oil as when it's hot, so you get more flow through the fan motor.
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