bottom corner of most raidators, there is a threaded connection. with a little thumb valve you unscrew, to let water/antifreeze mix to drain out.
remember antifreeze = poison to animals. and the antifreeze taste sweet to animals. so it is important you do not allow any sort of puddles to form up / be run onto the ground,
the little threaded connection on drain port allows you to connect a hose to drain port. and run hose to a 5 gallon bucket or oil catch pan.
most of my stuff vehicles to tractors. not placing a hose on drain port. normally results in water/antifreeze mix going all over the place (sub frame, belts, etc...) making a large wet mess.
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i generally start with a cold vehicle/tractor.
setup drain hose and catch pan or bucket.
get a garden hose ready,
make sure i have (antifreeze for refilling, and if need be anti scaling mix to add into the antifreeze/water mix when all done)
i generally drain everything out of radiator. then turn on garden hose, and let it run till everything runs clear out drain port. then plug drain and refill with water.
turn on vehicle/tractor, and set to a **high idle** to allow engine to warm up quicker but also to a point were the "thermostat" will open up. if you keep eye on engine temp gauge i generally can see a temperature swing, when thermostat first opens up. once i see the temp change, i will wait for a few minutes. then shut down tractor/vehicle.
drain radiator, and flush with clean water till drain port becomes clear. then pending on things i might repeat above. that or refill with water/antifreeze mix, and if needed anti scaling additive. ((if i do need to repeat, pending on how hot things are, i might let the tractor/vehicle set and cool down before draining the radiator))
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p.s. to note it, i generally use pure antifreeze vs the 50/50 already premix antifreeze. with above doings. so i can do a better rough adding of antifreeze and water, to get a 50/50 mix after all said and done.
