Could someone give me the procedures to change out the coolant

I opened the lower left hose from the radiator and the coolant was like black water and I want to change as it is is running hot.

I just can t figure out how to refill? the forum says u can not refill through expansion tank?

Then How?

thx

Kevin

There is a drain screw under the front cyl ( looks like a 6mm cap screw ... with a copper washer ) , and one on the waterpump cover . I usually just fill mine thru the tank ..... long as your not in a hurry. If I had black water in my cooling system I want to at least put a flush thru it , makes me think there has been some sort of electrollisis going on in there , or maybe the hoses are rotting from the inside out , but either way id look into that.
Hamish

Thanks