At my wits end with this. Replace 200ff blocks with 225 Pro Max powerheads on 25” bass mids with standard gear cases. Powerheads had/have less than 3% leakdown and perfect compression when I bought them. Mechanic strongly suggested “free flow” cooling which I believe is no thermostats or poppets? Lowered motors down to lowest setting. Replaced water pumps. Had top two holes of gearcases closed. Port motor is fine and operates with correct pressure and temp. Starboard motor. On hose, turn up to 2000 then 3000 rpm, no issues. Put boat in water, heats up at canal speeds with hardly any “pissing. Horn go off and temp goes up. Limp in on one motor. Back at dock in water, 2000,3000 rpm pisses and temp is fine. I have a guy who wants boat but will not sell it to him this way until problem is solved. Anyone have any ideas or suggestions? Thank you in advancd