shaenjay09
Seaman Apprentice
- Joined
- Jul 12, 2010
- Messages
- 48
hey guys. i put in a new thermostate and complete water pump kit on my 87 3.0l mercruiser i/o with alpha one cuse it over heated and wasnt sucking water. i replaced them and took it out 3 weekends in a row closely watchin the temp gauge and never got above 160 no matter what i did idled in gear full throttle everything. so i took it out today and when i idled the engine in gear it kept creeping up to almost 200. so i had to take it out of gear and it would go back down. when i gave it any kind of throttle it would go down. even a neutral in idle it was fine. just in gear idle. any thoughts what could cause that?