Motor dies when shifting into gear

[shader2199]

I have a 1983 80HP Mercury Outboard 4cylinder engine. The problem I have is when shifting into gear, the boat dies. We have tested for spark, and it gets spark when the trigger is advanced. It seems to lose spark when the trigger is retarded any. We replaced the trigger, and it still has the same issue. I can get it to start and idle fine. I just can't get it to shift into gear without dying. Any help would be GREATLY appreciated.

 

[racerone]

Open the carburetor slow speed mixture needles 1/4 turn and see how it behaves.

 

[The Force power]

There's no timing adjustment on those mercs. needed and as Raceone already mentioned the carbs.
Check the firing order & RPM when idle. You changed the Trigger make sure the wires are connected correctly.
Your motor will run on one-two Cylinders but not under load