I see by the description on the photo that it is a non standard fan. I think you have a bad modification and you need to take it back to original and solve the real problem. On my 51 216, the fan is about 3/8" from the rad. On my 38 Master, the fan is a lot further back from the rad and the fan does not have near the same area. I don't know why it works but each design was well tested.
