Re: 25 hp johnson 1978 model how can u tell if run hot?
Do you have a tell-tale hole to check for water uptake? Have you changed your impeller or looked at your pump housing recently? Also, are you sure you have your Carburetor adjusted correctly?
I would check the water pump/impeller issues first, and then I would consult the carb adjustment FAQ under Engine Repair/Maintenance. The article is
Carb. Needle Adjustment for Assorted Carb. Variations, and has helped out many a forum viewer smooth out their motor operation. Also, possibly check the fuel system (pump, hose, connections, etc.). A lot of us have cleaned carbs, and then found later that we missed that ooone liiiittle tiny gunked-up port.
As an afterthought, make sure you're running the right fuel/oil ratio with the right TCW-3 2-cycle oil and make sure your lower unit gearcase is well lubed. I once had a small motor that would cut out because my lower unit was getting hot and just barely seizing enough to make my motor cut out abruptly. I doubt that's your problem though.
Good luck!
