[Kube]

Originally Posted by aussie merc

fan needs to be as close as possible to the rad for best effect how ever you need enough clearance so when things move they dont get too close had similar problems with my 39 merc had fan spacers made to move the fan forward the other war would be to make a fan ring or a full shroud for the rad but be careful as the shroud can cause restricted air flow at highway speeds where as the ring doesn't but it wont use the full rad when idling

I'm willing to bet you had required a spacer as you had the fan that was supposed to be in a Ford of the same year. Mercury fans had a longer shaft.