Hey guys, I’m having an overheating issue on my 7.4L MAG MPI. I recently installed a new Bravo 3 outdrive on this boat, and it ran great for three days straight, no overheating. On the last day on the last ride of the day going back to the dock the alarm sounded and the engine was way overheated. Shut the boat off and let it cool down and then nursed it back to the dock.
My initial thought was the thermostat. I changed it the next morning and went for a test run and the minute I start putting load on the engine it started heating up. At idle it maintains a 175 temp. Took the boat out and decided to pull the raw water pump to see if the impeller was having problems (I replaced in at the beginning of the season). It was in perfect shape. I then took a garden hose and flushed out all the lines and water seemed to be flowing freely from both the engine side and the transom/outdrive side. Started the boat and could tell there was much more water coming from exhaust than the previous day. Took the boat to the lake and it did stay cooler on load, but at WOT it still overheats and in general is running hotter than it should.
I’m not sure what’s happening, but I’m suspecting the oil cooler or transom hose. Any thought would be great. Appreciate your help fellas.
My initial thought was the thermostat. I changed it the next morning and went for a test run and the minute I start putting load on the engine it started heating up. At idle it maintains a 175 temp. Took the boat out and decided to pull the raw water pump to see if the impeller was having problems (I replaced in at the beginning of the season). It was in perfect shape. I then took a garden hose and flushed out all the lines and water seemed to be flowing freely from both the engine side and the transom/outdrive side. Started the boat and could tell there was much more water coming from exhaust than the previous day. Took the boat to the lake and it did stay cooler on load, but at WOT it still overheats and in general is running hotter than it should.
I’m not sure what’s happening, but I’m suspecting the oil cooler or transom hose. Any thought would be great. Appreciate your help fellas.
