Ok so I have this new to me 20ft trophy CC the engine is in good shape not covered in corrosion it has been used in fresh water most its life then stored for around 5-6 years. I got it installed new impeller an housing out the gate as doing a look over I noticed the buzzer was unplgged under the dash thought maybe I bumped it installing new steering so I hooked it up. took boat out idles runs out at wot around 5000 rpm if I run over 4500 for any exteneded time I get the buzzer going off for over heat. I can hold my hand on the thermostat housing an not burn my self I have since installed a new thermostat an grommet an gasket and took the plastic plug out top of block an installed a tell tail. Take boat back out have awesome water pressure same thing if I run in higher rpms alarm will sound but I can hold my hand in the pee stream of water and touch the thermostat housing for a while at least 10 seconds before hot. no burning paint or anything like that. I pulled the plugs out they have no trace of water everything is good. so I took the thermostat out installed a stanless washer with a 1/2 hole to restrict watere flow a bit at idle to make sure block is full, I can run wot all day long now no problems or alarms are the temp sensors known to fail or get overly sensative or should I look else where. kinda stumped here. I just don't understand how it works fine with out the stat I thought that is what the spring was for that holds the stat seated was at wot the water pressure pushes the stat out against the spring to allow full flow.