Wiring in 2 fans.

Hey everyone, got a ? I want to wire in 2 fans so my monster Cleveland motor runs cooler. This is my weakest area in rebuilding. Should I run 1 or 2 relays, inline, seperate switches? I want to run them on a switch so I can turn them on, not to a thermostat. I thank you for your input.

 

You can do it how ever you want, but you need to make sure the components are sized for the correct voltage and current load. If your fans draw 15 amps continuous, make sure you use at least a 20 or even 25 amp relays since the fan will draw close to 20 amps during startup. 12 ga. wire (or even heavier) is also a smart idea to handle the current draw of the fans.

Here is a simple diagram for one fan. For 2, just add another relay and connect it to the switch. In your case, just replace the temp switch with a toggle switch under the dash.

 

Thank you, just what I needed!

 

Be Cool radiators has a good schematic online for two fans. Two relays....make sure your wiring is heavy enough. Do not set up fans to run when engine is shutoff, water is not moving thru radiator then so it is nota good idea to have such a huge amperage draw with no alternator charge happening.

 

Here is how I wired up my two fans. I have a switch that allows me to run it manually, I can switch it to run when rpm falls below a certain amount and I have a temp probe on the lower radiator hose that will turn them on when it gets too hot.