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Mariner 40 missing on one cylinder

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Nomoneymoreproblems

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I have a 1991 40 magnum 2 stroke 4 cylinder. It had been sitting for about 5 years. Just got it back from the shop for a new power pack. Carbs cleaned as well. Took it to the ramp and it fired right up. It would bog down after about half throttle so I initially thought it was high speed jets. Before I took them apart I figured I’d test the cylinders. There was a drop in rpms on 1,3,4. No change whatsoever on cylinder 2. Compression checked at 119,122,122,121. White blue spark on all cylinders. Now I have no clue. What would cause #2 to dead miss? Any help would be appreciated.
 
Did it have this problem 5 years ago???? Index the flywheel and check #2 to see if firing correctly, if it is then need to look at reeds.
 
I have the exact same problem on the #4 cylinder and I ended up tearing my motor down (1989 Mercury 40hp 4cyl, Same one). Funny that nothing looks horrible, but I'm replacing the rings and the reeds anyway, hopefully that fixes it. You sound like the only person that has the same problem.

PS: I've run it quite a lot and it seems to use a lot of gas, not sure if this is related but it would be nice to see if you have the same issue.
 
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The reeds looked good through the intake. I broke down and took it to a dealer. I think I was in a little over my head and would rather it be done right. I will report back with their findings though, in case it will help you.
 
Can anyone tell me what the 4 small brass “plugs” are for on the bottom right of the picture?
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Those appear to be caps that go on various places on the carbs, I can't recall exactly what they do from rebuilding my carbs but I'd leave them alone unless they are damaged. I think they most likely cap holes that were used for machining the carbs, although I am not completely sure.
 
There’s nowhere for them to go on the carb itself. Every machined area is either too big or too small for them. I found one after blowing with compressed air and can’t figure out where it came from. Both carbs are identical and everything looks the same on the outside.
 
Alright I will take a look on my motor, you may have the later edition carbs (wma 13 or whatever it is). I have the first series of carbs so maybe my carbs use the plugs and yours don't.
 
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