Hight Temp alarm sender

[lfd95]

Hey heres a quick question i have a 1999 340 twin 7.4 raw water cooled the port engine the over heat alarm goes off even though the temp gauge reads 170. i have checked engine with heat gauge and no part of engine is over 165 degrees. i assume the sending unit for the alarm is bad i also assume that there is a sending unit for the gauge as well as the alarm. i know that the sending unit for the gauge is on the port side of the block, i thought that the sending unit for the alarm would be in the thermostat housing but i dont see it there??? any thoughts?????? thank you all Scott

 

[testlab]

I have the same problem but I have fresh water cooled 7.4Ls. There are two sensors on the thermostat housing on mine, not sure about the raw water cooled models though. Do you have the Sea Ray monitor panel? I do and it's the non-repairable potted one and it's shot, only the port over temp is problematic but since I can't silence the buzzer I had to disconnect it.

 

[280Mcclinton]

I am having the same issues with fresh water cooling. I was out last night and starboard engi engine alarm went off with boat load of people for fireworks. Gauges fine and boat ran fine. Just alarm going off for temp. Gauge said temp gauge. So if I read your reply are these not repairable?

 

[280Mcclinton]

I am having the same issues with fresh water cooling. I was out last night and starboard engi engine alarm went off with boat load of people for fireworks. Gauges fine and boat ran fine. Just alarm going off for temp. Gauge said temp gauge. So if I read your reply are these not repairable?

 

[testlab]

Which panel do you have? I suspect yours will be quite different to those in our pre2000 boats. First thing to check for is always a bad sender. It's all very different yet again if you have Smartcraft fitted.