Just fresh water, thats all -you don't need antifreeze. You want to change the oil in a four stroke. Also the gear oil in the "foot"- lower unit. Check for water in gear oil, the seal may be leaking, if possible pressure check its easy and worth the price of a pump and gauge. When Checking the lower unit use the right size screwdriver and check the paper gasket, many times some won has striped the stainless screw plug, replace if worn. Run the engine out of fuel and spray lube in the pistons and turn engine over by hand to coat cylinder walls. last grease all fittings and wipe down with a cleaner wax.
