Technical ? about H2O temp sender for auto on fan and temp gauge monitoring

I know this may be a dumb question but here goes anyway:
I have a 50 Merc with a 302. The previous owner had the electric fan wired to a toggle switch on the dash. I didn't like that so I bought a Painless wiring kit for an auto on/off instead. My question is this... with only the one sender, how do I monitor the water temp as well? Do I need a 2nd sender somewhere else or just run 2 wires off the sender unit - 1 to the relay for fan and 1 to the gauge?

thanks for humoring me...

 

The sender you have is s switch that closes at a set temperature.
You need a second sender for a gauge.

 

Do you have a temperature gauge now?
If so you will add a temperature SWITCH
This turns off and on the relay which in turn turns off and on the fan.

 

I had a clearance issue and had to install a pusher electric fan in my fairlane, after a 351w, AOD swap, can someone tell me where to put the fan temp switch, since I've already used the manifold spot for my temp. gauge?

 

If you have a brass rad, solder a bung into the lower tank of the rad. Rad shops should have these in 1/4" or 1/2" NPT.

Sent from my SM-T350 using The H.A.M.B. mobile app

 

I put mine in the drain plug on the radiator. It's adjustable, so I set it watching the temp gauge in car.

 

The temperature SWITCH grounds the fan circuit turning on the fan.

 

On mine, the temperature switch grounds the relay for the electric fan. Not all temp switches can handle the amp draw of an electric fan.

.bjb

 

The fan control should be done through a relay so it has low amperage draw.