Well now I have to figure out why it stays on. I think it is wired correctly. Tan from engine and purple from key switch. Probably why the previous owner disconnected it. Not sure why he wouldn't have just disconnected the purple wire from the key switch. Instead he disconnected both and discarded the alarm.

Looks like Optimax has 2 temp sensors. Is there one on each bank? Parts diagram I looked at just said sensor and quantity of 2.

Thinking about just replacing all the sensors. Seems to be a common issue with these motors.

Are you getting a warning with key in on position without the engine running or is engine running and if so is it a solid horn or a intermediate horn...OPTI

solid warning with key and motor running or not. Makes me think it is a temp sensor not the oil tank sensor. I am guessing that it should just beep beep like my Black Max did when I turn key on. I have read that someone had to clean out some hose on the lower portside on the back of the motor. I want to say it is a grey hose.