Anyone have this issue? Problem is consistent, whether I let it idle for a couple minutes on the trailer or throw it in reverse right after startup(usually because of other boats waiting to launch). This only seems to happen when backing off the trailer(even if I put it in Forward instead of Reverse it will run very rough and sometimes stumble and die.). Rest of the day fishing never an issue. Right now to prevent it from killing the motor, I throw it in Reverse til boat is floating off trailer, then immediately put in Neutral for a few seconds. Works OK after that. Symptom occurs in hot and cold weather/water.
Same issue on my previous Merc Optimax 200, however, if I let it warm up a couple minutes it would not display the symptom. I chalked it up to thick, cold oil; maybe clutch dog unable to engage properly.
Had 20 hour service done last July, dealer said its 'normal'. This is a popular motor around here, and I have not noticed others having this issue.