fan override switch

[turbowop]

What would be the easiest way to tackle this? I want stock radiator fan functionality retained for both my AC (pusher) and radiator (puller). I'm going to install a 180* thermostat so I just want to wire in a switch to flip the fans on when in stop/go traffic or waiting in the staging lanes at the track. My coolant temps are perfectly normal for a stock car, but I'd like to get them down a bit during those driving conditions. I'm sure all I have to do is run a wire to the fan relays, but I'm not sure if I should go to the relays or to some random wire under the hood that's maybe easier to access. Anybody else done this?

 

[Jason G.]

IIRC, the single wire sensor on the back side of the t-stat housing closest to the cylinder head will run both fans when grounded.
Maybe wire in a switch there?

 

[brisvr4]

^^ correct. I use an old power/economy switch in the console to activate mine. It also runs both fans on high.

 

[mitsuturbo]

Quoting Jason G.:
IIRC, the single wire sensor on the back side of the t-stat housing closest to the cylinder head will run both fans when grounded.
Maybe wire in a switch there?



This is precisely what i'd do. If you're worried about the factory function of that temp switch, leave it plugged in, and simply tap in a wire that will go to switch. Wire the switch to ground. Enjoy.

 

[toybreaker]

Quoting Jason G.:
IIRC, the single wire sensor on the back side of the t-stat housing closest to the cylinder head will run both fans when grounded.
Maybe wire in a switch there?



... fwiw, this will also kick off the a/c compressor

 

[mr.mitsu]

Does anyone know the colour of said wire???
Thanks

 

[mitsuturbo]

I believe it is blue.

 

[turbowop]

Thx guys. Looks like I have a little project for the weekend. /ubbthreads/images/graemlins/smile.gif

 

[turbowop]

I went and looked in the engine bay. Rather than run a wire all the way to the thermostat housing to tap that wire, is there a place closer to the fuse box under the hood that it's accessible? I did pull that wire off the switch to confirm that it turns on both fans when grounded, so I just need to find a closer place to tap into it.

 

[misterfixit]

From the a/c compressor controller.

Rich