Can anyone tell me when the cooling fan should kick in!? I had to change the radiator yesterday due to a cracked tank. When I filled up the bottle with anti-freeze, I ran it for a few minutes until it warmed up on the needle with the Heater going on high, to make sure the circulation was there. Once I turned the heater off, about 15 minutes later, you could definately see that the thermostat opened, because the collant dropped about 2 inches or so in the bottle when you hit the gas to about 3K.

About another 10 minutes or so after that, the liquid in the bottle boiled over, and I had to add another gallon of 50/50. The fan(s) never turned on up until this point. At what point should the fan(s) have kicked in!?

When engage the A/C system, both fans spin perfectly fine.

 

Cooling fan(s) should come when a/c is on provided it works or when coolant temp reaches approx 226F and should run til temp drop to approx 208F.Hope it helps