[Michael C Henry]

More info- Relays are powered with Master and ignition on. Thermostatic switches will turn on it's relay when they sense radiator reaching temperature set with adjustable switches . Dash double pole double throw switch is used to go ahead and turn fans on, lower pair or all. two thermotic sensors located in radiator, connected to two adjustable switches that will turn on the two relays, Dash switch uses the same connections on relay to have fans running with out the thermostatic sensors reaching the adjusted temp points.
I went on a cruise last year, and had problem with the engine getting too warm While crawling through a City Park. I found the plastic circuit breaker holder for the four circuit breakers (on the fire wall) had been mounted using the electrical terminals. The terminals got warm, melting the plastic brackets that then gave way, causing an even worse electrical connections. I had the plastic circuit breaker holder crushed in with the wire terminals. Didn't work out Metal to metal now.