Hi, looking for some info re the thermo switch/ ovrheat sensor. I have a mid 80s 2 cyl mariner(yamaha) 40hp 2 stroke. There appears to be provision for a sensor to be fitted to this engine. Were sensors ever fitted to this engine and if so did they just measure the temperature of the metal cylinder head as opposed to the cooling water? I have a pink wire under the cover which i imagine this would connect to. Any info gratefully received.