Old Mercury 25 hp - Fuel Issue

[kubmer4488]

A late 70's/early 80's mercury outboard (electric start & serial #B101419) 25 hp dies at various times under load and idle. The local merc shop indicates that all is well. After a carb tune and test run the motor ran flawlessly (about 3 hour of running). The next trip to the lake the motor stopped, hard to start, and had to choke to keep running.
Can anyone determine the year of the motor and possible solution to this problem.

[boats.net]

It's a 1986, Run a compression test first, if choking keeps it running then carb has plugged jets or passages.