from the top to the bottom
Once the thermostat has opened, the hot coolant flows from the thermostat housing on the engine into the top of radiator and out the bottom of the radiator back into the water pump.
The water does not flow through the radiator until the engine is at operating temperature. At that time the thermostat will open and allow it to flow.Sometimes you are unable to see it, depending on the direction of flow. Increase the engine rpm and you should notice a change.
no
It flows in the bottom hose of the radiator and out the top hose.
direction of flow
Coolant flows into the water pump thru the bottom radiator hose, into the block from the water pump, up into the heads, and then to the intake crossover (or heater core from the back pass side head), then back to the radiator via the top hose. Coolant from the heater core is returned to the water pump not to the radiator.
Where the ground water leakage direction meet into the surface water is called Base flow.
Coolant is drawn into the water pump via the lower radiator hose, the water pump pushes the coolant thru both sides of the block and up into the back of both heads, thru the heads then out the front of the heads into the intake manifold then thru the thermostat and into the upper radiator hose into the radiator.
South
The boiler has a circulation pump that circulate the water
Water always flow from a higher elevation to a lower elevation.
In a river or stream, the flow of water is in one direction only.