1988 150HP bogs down under load

[214fishfool]

I have a 1988 yamaha 150 hp that bogs down under load. Other motor on boat runs great. Initially was getting fire on only 3 cylinders.Changed cdi unit now getting fire on all 6 but on 2 of the 3 that were not getting fire initially the spark is not near as good as on the other cylinders. Could this be a coil or stator problem. Have already changed spark plugs, fuel pumps, and cleaned carbs. Any help is appreciated.

[boats.net]

Check compression to see if compression is even. Bogging is usually a fuel problem, carbs or fuel pumps.

[214fishfool]

Compression check is good. Have already took off carbs and cleaned them. Runs great when not under load. Could this be a coil issue?