Fan sits behind Rad, and air comes from outside through the rad.Mine was not working, but when we got it working, were VERY surprised to find air blown from the engine compartment, through the Rad to the outside!!. By the look of things, this had been like this for a very long time.Why was it not noticed before?. Probably because the fan very rarely comes on in normal driving, and never came on when on track. Having said all that, I didn't work anyway!!!.With my dogged English Spirit, we will get there.( For you young whipper snappers, that means, we will keep going, and get there soon!.)