The shop has no clue as well as tech support at mercury. The basics,
225 compression in all 3 cylinders plus or minus a little but strangely high
Somehow 0% leak down in #1 and 2% the rest
Perfect spark with carbs completely cleaned and inspected
Timing is good, valves didn't even need adjustment
Complete carbon clean and soak over night of all cylinders resulted in next to no carbon release
So the issue is the boat will run then suddenly #1 falls out. Sputtering between 2000 and 3200 rpm. Often it will finally kick in power but then when you pull back it just dies. While the problem is occurring it can't break 3200 rpm. The problem is intermittent but happens more than not. Maintains spark according to timing light and priming while the issue occurs does nothing so fuel supply is there. Shop is stumped as am I. Any thoughts?
225 compression in all 3 cylinders plus or minus a little but strangely high
Somehow 0% leak down in #1 and 2% the rest
Perfect spark with carbs completely cleaned and inspected
Timing is good, valves didn't even need adjustment
Complete carbon clean and soak over night of all cylinders resulted in next to no carbon release
So the issue is the boat will run then suddenly #1 falls out. Sputtering between 2000 and 3200 rpm. Often it will finally kick in power but then when you pull back it just dies. While the problem is occurring it can't break 3200 rpm. The problem is intermittent but happens more than not. Maintains spark according to timing light and priming while the issue occurs does nothing so fuel supply is there. Shop is stumped as am I. Any thoughts?