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1981 50 hp johnson stalls after starting

I've had it 8 months and it's been on the water a 10 or so times. Sadly it was in much worse shape then I had hoped/thought. When i looked at it, it had a bit of a backfire and it was at a boat shop so they said they would get it fixed. They replaced the power pack and it sounded ok the next visit. I hoped I wouldn't have to many other items right away. Well some issues with the boat itself slowed me getting it in the water but the engine still seemed ok.
I've had good trips and bad trips. I have replaced the fuel filter, rebuilt the carbs ( not just sprayed them) with kits and soaking & scrubbing, replaced most of the fuel lines, water impeller of course, coil packs,plugs. The compression is 130 and 135, the spark jumps a 7/16 gap well.
Got stranded on one trip started out good, stopped to fish and no response when started. get towed in. Had no spark, ended up replacing the stator with a used one. Upon starting it back up it seemed very hard to start. I had always felt like it didn't idle perfectly, the control cables are not real responsive and spent some time trying to readjust the cables and settings. Thought I had a good setting for starting and running. Replaced the starter( on it's last leg). Right around the time of the stator replacement I started noticing unburnt fuel/oil on the front of the leg.
Three more trips out, lots of stopping and starting, seems good on gas, went out yesterday and started good, off we went. Ran about 4 miles out and dropped the idle to stop and it stalled just as I was going to shut it off. Had to be towed in again. Every time starting it, ran a moment and stalled. The throttle advance was not giving it much gusto. At full advance it's stalling in a hand full of seconds, at no advance it stall right away. Bulb is pumped up easily and firm. If I manually increase the throttle I can keep it running but it's rough and not up where it should be with the controller set at full. If I manually close the choke to about 1/8 from closed it picks up and levels off smooth. So my assumption is I am very lean from an air leak somewhere?
I have replaced a fuel connector on the motor that had worn o rings, no change. Ran it on a different gas tank, no change. Checked the carb bowls they are getting and holding fuel. Pulled the carbs and pulled them apart verified everything is clean and set correctly, checked smaller fuel lines. I had three good trips then this popped up. The reeds look good. Where could I be pulling what seems like a lot of air in to make it so lean?
Thank you for any thoughts on this.
 
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Note: If a air leak/vacuum exists... you will by the same token also have a fuel leak.

Assuming that you have compression and spark as you've explained... and that you're using the proper Champion QL77JC4 spark plugs set to a gap of either .030 (long life) or .040 (strong spark)..................

Temporarily back the throttle roller away for the metal cam. Make sure that the throttle butterfly linkage between the carburetors is adjusted so that the throttle butterflies open and close at the same time.... you do not want one butterfly completely closed and one ever so slightly open.

Adjust the throttle roller so that the butterflies just start to open when the scribe mark on the metal cam is dead center with the throttle roller... not before or after.

In cleaning the carburetors..... if you did not manually clean the high speed jets that are located horizontally in the bottom center of the float chambers, way in back of the drain screws, with a piece of single strand wire.... do so as solvent and pressurized air just doesn't do that job properly. Those jets are removable via 1/4x20 threads.

Let me know how you make out.
 
Note: If a air leak/vacuum exists... you will by the same token also have a fuel leak.

Assuming that you have compression and spark as you've explained... and that you're using the proper Champion QL77JC4 spark plugs set to a gap of either .030 (long life) or .040 (strong spark)..................

Temporarily back the throttle roller away for the metal cam. Make sure that the throttle butterfly linkage between the carburetors is adjusted so that the throttle butterflies open and close at the same time.... you do not want one butterfly completely closed and one ever so slightly open.

Adjust the throttle roller so that the butterflies just start to open when the scribe mark on the metal cam is dead center with the throttle roller... not before or after.

In cleaning the carburetors..... if you did not manually clean the high speed jets that are located horizontally in the bottom center of the float chambers, way in back of the drain screws, with a piece of single strand wire.... do so as solvent and pressurized air just doesn't do that job properly. Those jets are removable via 1/4x20 threads.

Let me know how you make out.

The spark plugs are indeed the champion QL77JC4 set to .040
The carb linkages are set to speck as per the official OMC service manual for the motor.
And I always use a bread tie stripped of its plastic to help clean/clear out the jets.
And I have thought the same thing about the leaking fuel but can find any leaks and the fuel line holds a tight enough seal that when disconnected it sprays fuel all over me. I'm just stumped on this thing.
 
OK pretty sure I have the culprit. The electric choke is sticking closed. The rod with the spring had to be pulled at to release it, then it purred again. Now I have removed the choke and it had what looked like dirty graphite on/in it. I have cleaned it carefully but I still get a now and again sticking of the rod. The manual says no lubricants because it will attract dirt. Any suggestions other then buy a new one for $120
Thanks
 
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