Riding at 4000 RPM and overheat sensor goes off, throttle idle drop off kicks on. Waited, Horn stopped, Started back to ramp. Overheated at 3200 RPM. Noticed pressure gage is below 10 PSI at idle. Plenty of pressure coming out of pee hole. Pulled lower unit and impeller looks O.K. Same problem last year. Read a lot about Pressure Control Valve. Removed and cleaned it. Looked pretty good. Replaced thermostat, o/heat sensor, water pump. Ended up with 18 PSI and o/heat went went away. Run in saltwater only. Have built in engine flush kit and use it religiously when I get home from running boat. Don't want to pull head to see if water ports are plugged. Yamaha's known for snapping head bolts. Any suggestions?
