40 Hp will not idle

[rollercoaster]

Mercury 40 hp will not idle unless i give it a little throttle.
When I remove plug wires from cylinder 3 or 4, engine continue to run. Removing plug wires from cylinder 1 or 2 causes engine to die out. Engine run when giving a little throttle. I have limited skills on engine repair. I did replace the switchbox and stator on this engine last year.
Thanks

 

[beckerjs]

Check pm


cyl 3 and 4 are not working for the following reasons, spark most likely, fuel if the engine has sat, compression if you ran it with dirty carbs.