Re: change water pump and no water go to the piston?
Remove the T-stat and see if it still overheats. If so, drop the lower unit again and check out the water tube and make sure the impeller key is installed.... If it's does not heat up, get a new stat... Water pump runs anytime the engine is running, no matter what gear you are in, even neutral. Do NOT run the engine for long until you find out what the problem is. It will die a quick death. Just run it long enough to see if it's overheating...