I was told by two different mechanics not to run the motor while using the garden hose attachment as a source of cooling water. Don't know why??? But since two mechanics from different dealerships both said the same thing, I would at least double check before doing it.
i used to anchor my boat on a muddy clam flat and push mud and silt thru often. dont let it run for a minute or two without water pumping thru it' that only heats up the rubber and destroys it. i used to carry a 4 foot section of weedwacker cord to run down thru the hole to unplug it when it jammed up with debris. learned that trick watching bonefish guides running flats boats over very skinney water in the bahamas