Bringing a '74 back up to her intended glory.

Bmachine

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Progress! Since I knew that most of the parts were new, assuming there was no issue with them and that the condenser fan was coming on as soon as the AC compressor was activated, I started wondering if it could something very simple like... the fan spinning in the wrong direction. It is very hard to tell by yourself so during lunchtime I had a coworker help me by turning the AC on and off while I watched through the front grille. And sure enough, the condenser fan is pulling air out towards the front of the car, thereby going against the engine fan which is pulling towards the engine! Doh!

So either I ordered the wrong fan or I was sent the wrong fan. I guess the quick (albeit temporary) fix will be to reverse the wires to make it spin the other way...
 

Bmachine

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Good news. I was really not looking forward to replacing this condenser fan with another one since that would involve draining the coolant, removing the radiator and all that. But going back to my original order for this, I noticed that this was officially a "reversible" fan. So just switching the wires should take care of the problem. Or, at the very least, get both fans in sync...

Next job will be to figure out how to use the sensor/bung at the bottom of the radiator (yes, it is there... but not connected to anything at this point) to trigger the AC fan when the rad gets too hot even with the AC off.
 

HB Chris

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Your 74 had a control box near the coil to control that temp sender, we have a wiring diagram to use for earlier coupes, we just add a diode.
 

Stevehose

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See if it still overheats with the fan now going in the correct direction. In 95 degree heat and humidity here, idling with or without a/c does not cause much more than a blip in temp so I've never needed to wire one of these up. I have an aluminum radiator and the 9 blade fan upgrade. Stock condenser fan.
 
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