Where is the coolant drain plug on 2001 arctic cat 500 ATV?

If it's the suzuki 500 engine, it's down on the right foot area. Follow the coolant hose around the oil filter and down where it attaches to the water pump. There is a 10mm bolt, pointing downwards, underneath the water pump.

Remove this bolt before removing the radiator cap, this should keep the messy draining to a minimum. I would suggest having a wide container to catch splatter to also help keep the mess small.

Hope this helps you out.