BAD MECHANICS - Thermostat and Radiator Fan Blade

Need correct Radiator, shorud, Fan clutch, fan, thermostat housing,
Properly setup the kick down linkage ( the rod should be forward at idle not in the back of the slot ) .Really, Get out the service manual and see what else is wrong.
If you do it right you will only have to fix it once.

Yes, the kickdown linkage should look like this - and it should have a light spring to pull it forward (you can see mine just under the kd rod. The way the OP's is hooked up, the kickdown cannot possibly be working right, and maybe not at all.

1704401229466.jpeg