fan mounting/cooling

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Post Sat Apr 13, 2013 7:20 pm

Ive just come to fitting my 16" electric fan its fouling the front pully, the only way around this ive found is to put the fan on the outside... still with the fan shouding fitted... will this be sufficient and will it be ok for all round use track/road?
ross_jsy
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Post Sat Apr 13, 2013 7:21 pm

Will be ok, just make sure it's pushing air through the rad, not sucking.
Bristol_Jer
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Post Sat Apr 13, 2013 7:23 pm

I've got a 16" fan in front of my rad, works perfectly, just make sure the fan is spinning the right way if you are turning it round from behind to in front of the rad.
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Post Sat Apr 13, 2013 7:24 pm

Too slow at typing lol :D
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Post Sat Apr 13, 2013 7:52 pm

Electric fan mounted in front of the radiator needs to push rather than suck...as the actress said to the bishop....I find that this set-up works fine with my M50'd touring.
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Post Sat Apr 13, 2013 7:56 pm

So I need to make the fan suck hot air out through the rad or shall I leave it so it still pushing the air through?

Forgive me for beeing thick but are fans meant to blow the air form the engine bay out through the fan.... if so will it be ok for the fan to now blow through from the out side into the bay? Or does the fan suck air through the rad into the bay therefor itl now suck air through the rad from the bay to the outside...
ross_jsy
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Post Sat Apr 13, 2013 7:59 pm

With it mounted on the front, you need it to blow the cool air from outside the vehicle into the engine bay through the rad.

Edit, just hook up the wiring so it does this. The fan will be fine doing it, a lot of manufacturers do it like that.
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Post Sat Apr 13, 2013 8:11 pm

Awesome so on the back of the fan just swap the red and the black round?
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Brianmoooore
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Post Sat Apr 13, 2013 9:07 pm

Reversing the polarity of the supply to the motor may cause it to run backwards, but if the fan is of any kind of decent design, it won't move air efficiently when turning in the wrong direction.
A fan of any kind isn't normally required on any car with a front mounted radiator for most of the time. The forward motion of the car is sufficient to force air through the radiator, and a powered fan, whether engine driven or electric, is only required for when the engine is running and the car not moving or moving slowly, so make sure it's thermostatically controlled. Don't underestimate the power/fuel that a fan takes to drive it.
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harry_p
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Post Sat Apr 13, 2013 9:10 pm

Just watch the temps, a lot of fans will spin in reverse but they won't push anywhere near the same amount of air.

Properly designed reversible fans have either a special blade profile, or they can be removed and mounted the other way to match the reversed polarity.

I had a 14in spal pull fan on my m3, it worked perfectly, but I wanted it more like the oem setup so mounted it as a push and reversed the polarity.

On a warm day it would hold the temperature, but it wouldn't actually cool so one it was on it stayed on, which I wasn't happy with so went with a different solution.
cheers,

harry
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Post Sat Apr 13, 2013 10:43 pm

Ok cheers for all the replies guys... Ill have a play with it, It did come with a adjustable temp switch.
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Post Sat Apr 13, 2013 10:50 pm