Radiator Fan Control, Off When not Running

[BBShark]

I would like to turn my radiator fans off (even when hot) when the engine is not running. Thought about putting them on a pressure switch but I'm not sure how long it takes, after the car is turned off, to bleed down. Trying to keep the fans from coming on at the same time when restarting.

Maybe some kind of tach driven sensor?

 

[BBShark]

Found something that I think will work. A 0-10 second adjustable delay. So I can restart a hot car (both fans on) and delay Fan #1 for 5 seconds and fan #2 for 10 seconds.

$2 each!

 

[BBShark]

I got the module and it works as advertised. There is a 0-10 second delay in turning the fan on (or anything else). So, when I restart the car and it's hot, I won't be switching power to the starter and both fans simultaneously. Plan is, start the car, fan #1 comes on in 5 seconds, fan #2 comes on in 10 seconds.