Switched to Power - wiring question

[Walter Moore]

I think that with our car's older style "cold in the bottom - hot out the top" cooling system there will be some coolant circulation just by convection so long as the fans are running and cooling the fluid in the radiator.

In either case pump running or not, as soon as the thermostat closes all circulation stops.

[ktm]

Ron, it is a little inconvenient but I get over it. My engine management system controls my fan. It switches the relay ground based on the temperature I set. I am running the Flex-a-lite 210 dual slimline electric fan. I can set my temperature point, so if I am finding that my fan is cycling on and off a lot, I can drop the temperature or raise the temperature a bit to reducing the cycling.

While the engine may not get any hotter, the coolant certainly can and does. This is what I meant by keeping the coolant from boiling over. The moment you shut off the car, the coolant stops flowing yet the head is still the same temperature. Since the coolant is no longer flowing and the car is not moving, the coolant temperature starts to rise.

[V8-240Z]

I think that with our car's older style "cold in the bottom - hot out the top" cooling system there will be some coolant circulation just by convection so long as the fans are running and cooling the fluid in the radiator.

In either case pump running or not, as soon as the thermostat closes all circulation stops.

The thermostat will not close until the engine has cooled down. Relying on convection is why the fan will repeatedly turn on and off once the engine is off. With the electric water pump running after shut down the engine is quickly cooled down and the fan only runs once for a surprisingly short time.