90_Mustang_GT

Just purhcased an electric water pump, and with that i put on a new 2 row aluminum radiator. My fox is supercharged. I was gonna have my electric fan run the water pump. What are the thoughts, or do i just run 2 seperate switche?

BlessedHellride

to separate sources of power. I would put the electric water pump on a key on power source also.

Portmaster

Both need their own relay. Water pump needs to be activated any time the key is in the run position. Fan needs a thermostat so it will continue to run until the radiator cools down to a set temp

mjr46

I run 2 seperate relays both that are activated by switched 12v, that way I can run the pump with engine off for quick cool down times, I used a 30 amp relay for the pump as well as one for the fan= dedicate 2 seperate circuits to do the job

90_Mustang_GT

Thanks guys. The thermostat for the fan to kick on and off i got, what about the water pump. What do you guys use thats hot at all times, with key on?

BlessedHellride

You can use the red wire going to the windshield wiper motor, it's hot all the time. There is a hot wire for the alternator also, but I don't use my stock alt. harness, only reason I said that. There are key on hot wires all over the engine bay and under the dash. Run the wires(small) form the key on wires to the relays. Two separate circuits. Run heavy hot wires from 12vt source to the relay and to the accessory you are powering. I have to 40 amp relays on my twin electric fans. A bit overkill, but it sure runs cool.

cch

I run my electric fan and electric water pump solely using my accessory drive on my ignition. When I turn the key both comes on at the same time, no switches required.