Hello guys... Wow i am having the exact same problem. I took my boat out for the first time last sunday and that happened to me as well.. The temperature goes from 160 to 240 when im idle. I was about to start a thread asking for some help but i found this one and i will check for what you told...
I recently bought a 1990 Monterey 19footer. And its been hard finding info on this boat. Im new at boating. So my boat comes with the 4.3 L Chevy V6 motor and a 260 mercruiser sterndrive. I recently changed the motor oil and someone recomended me to use 20W 50. So i did. But i wanna make sure...
