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A Quick Test to See if Your Electric Fan Sucks

2011 April 12
by admin

Here’s a quick test to see if you’ve wired your electric fan to draw air the correct direction through your radiator, and to get a rough idea of whether it is pulling enough air to keep your car cool. All you need is a sheet of 8.5×11 inch paper, a fully-charged battery and a short safety check list.

Turn the power to the fan on (you may have to temporarily install a manual override switch, or bring your engine up to temperature so the thermostat turns on the fan). Make sure the engine is turned off for your safety. Place the sheet of paper on the side of the radiator opposite of the fan.

If it stays in place, you’ve wired the fan with the correct polarity, and the fan is moving pretty good air through the radiator.

If it blows off, you have the fan wired backwards.

If it doesn’t blow off the radiator, but it slowly falls away, the fan isn’t pulling enough air through the radiator. There can be quite a few causes for that, which we cover in the video.