Flex fans do a real good job of not moving air. If you do have a stock fan to swap in, try that.
My brother has a factory fan not currently being used; not sure what diameter or blade count. I can try it with the clutch and see how it goes.
Putting a stock fan in place without the viscous clutch would be a worthy experiment, especially if it is the 18 inch diameter/ 7 blade unit.
How would rate your own or nearby available metal working skills?
Could you cut down the outer edges of the blades of a 9 blade Ram/Dakota fan and find the equipment or shop to re-balance it?
Or re-drill the bolt holes of a Ford/GM/Toyota fan?
The purpose of the K thermocouple probe on an IR-unit is to be able to IR read the temperature of a spot,
then switch to a probe to touch that same spot and find out how off the IR reading was.
IR units with “emissivity” adjustment are also preferred for this reason.
Low end IR units have the emissivity set at 0.95 without adjustment.
Use your present Craftsman IR unit to scan your warmed up radiator and look for “cooler regions“ that might indicate internal coolant flow blockages.
