From the Summit description:
"....................symmetrical design, ................can be mounted as a pusher or puller, with no need for blade flipping"
If the above is indeed your fan, what this means is, the fan blades are equally poor in both directions. There is no such thing as a well designed, reversible blade. All well designed blades are "cupped" just like an aircraft wing, and are only efficient in ONE direction
Look at the mechanical fan you took off. It has a definite front and rear, and I can assure you that if you turn it around (rear of blade facing front) It will STILL pull some air through the radiator, but not nearly as much as when properly mounted.
One has to wonder if that fan can really move that much air.
