I am trying to repalce the fan clutch. I took it out but I have trouble removing one of the the 3 allen screws that holds the blades on the clutch. The screw is stuck and the inside of the allen bolt is rounded. I used anythink posible like WD40, brake fluid, trany fluid but I can't get it open. I do not want to spend $40 on a new blade neither to wait 10 days for an ebay aftermarket blade for$15. Any ideas????