[alanmay0]

Hello again, I have a 1967 GTO with factory AC. I am confused as to what size diameter the cooling fan should be. Ames shows a 17.5" for 64-67 and they also show a 18" fan for 64-76. I currently have a 19 1/2 in 7 blade in my car.

I am having an issue with the clutch fan coming on when driving on the highway above 60 mph with the AC on. I have changed out the clutch but it still does it. The water temp. gauge shows the water temp to be around 180-190, not hot for a 90 degree day with the AC on. I have put a 160 degree thermostat in the car but no changes.

I am wondering if maybe the fan diameter is too big. I read where you should have 1" space between the end of the fan blade and the shroud, is this correct? Mine have about a 3/8" clearance.

My fan blades are about have way inside the shroud and half way outside, this I have been told is correct.

So any suggestion as to why my clutch fan comes on while driving on the highway??

ps I have also changed out the water pump just to be sure that was not the problem.

This problem started when I was told that my ac condenser should be within 1/2 " from my radiator. wHEN i MOVED IT THIS CLOSE IS WHEN this problem started. Now the ac temp is much cooler with the condenser closer but the clutch fan engages on the highway.

thanks
alan