My K has an electric fan (not thermo) mounted under the guard.

it's a bit rattly and needs replacing. probably a stupid question but......

should it be sucking air through the radiator and out of the engine bay, ie aiding the stock fan on the water pump...

or should it be sucking air from the wheel well and into the engine bay?

also is there an easy thermo switch to install when i install the new fan and what temp should it kick in at? i'm pretty sure my car has a 65 thermostat in it..

cheers.

The fan can work either way, either sucking or blowing. The fan will pull more air than it can push.

You should make sure it aids the stock fan by sucking air from the engine bay through the radiator and out into the wheel arch.

Are you sure there are 65°C thermostats? The lowest I've seen is a 74°C one (they are stamped with the temp if you pull your's out). You could have a well sorted radiator in your car. I have a 82°C thermostat in my car, but on a cold day it can run at 55°C and on a warm-hot day it'll sit on 71°C.

If it were me I'd tell the fan to come on at about 90 - 95°C. If you're cooling system is properly sorted it shouldn't really need an extra fan IMHO.

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"In two years time your car will be like a lady's clothes, out of date, my car will still be in fashion when I am dead" - Sir Alec speaking to Pininfarina

It should be sucking air from the engine bay & expelling it out the wheel arch, otherwise it will not only be fighting against the crank driven fan but also against the natural flow of air when the car is in motion.

I have a Jaycar kit for my next thermo fan installation
http://www.jaycar.com.au/productView.asp?ID=KC5381&CATID=25&keywords=&SPECIAL=&form=CAT&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=347
Haven't fitted it yet, but it has adjustable temperature switching and importantly adjustable hysteresis so it should do the job well. Have just discovered my water pump is leaking, so in the next couple of weeks I will fix that & remove the stock fan and fit the thermo fan.
Will let you know how it works out, but thermo fans are definitely the go!

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Too many cars, and too little time.