I have a 1994 Mercury Tracker, 60 HP, three cylinder. Its oil injection system has been removed and I mix @ 50:1. It runs quite good, as long as I stay below 3800 PRPMs. Above that, the overheat alarm sounds. The alarm stops within 20 seconds of idling in neutral. I could run all day below 3800 RPMs. I suspect my alarm may be faulty. I brought it into the kitchen and did the hot water thing. It triggers the alarm @ 170 degrees. I don't know if this is right or not, but my sensor measures metal, not cooling water and I've come across a few references to heat sensors of this type not activating below 260 degrees and 285 degrees. The temperature sensor for my motor ( according to Boats,net) is Mercury part #78799 2. Does anyone know the temperatrure required to trigger this sensor? If not, does anyone know the typical temperature range for a metal temperature sensor?
Any thoughts will be much appreciated.
Any thoughts will be much appreciated.