Heat Alarm wire..
 

So I figured out that my boat the heat alarm isn't hooked up..and I found that out after looking down at my temp gauge hitting 230 degrees...I have a thunder bolt ignition...does anyone know the heat alarm wire color to hook up??

I assume you mean the high water temp alarm????

There is a Merc alarm sender that installs in the intake. Then the tan wire with blue stripe connects to the sender.