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BF50a SHAKES AT IDLE + REVERSE BINDING

One other thing i took a laser thermometer and around the top cylinder water jacket near plug it’s like 185 the bottom two are like 160. Not sure if this is related. Have taken off my water jacket and cleaned it all out and replaced anode yet since i got it…kinda scared to open it up
 
So for awhile my old flywheel was hitting the two large coils underneath it. Could one of those be damaged/failing. This whole problem reminds me of a bad/corroded distributor on a car…heat degradation
 
Here’s another thought…i mentioned when i pull the wire on the middle cylinder it doesn’t change the running much…just slightly. I thought maybe bc it’s the middle it is more balanced and less noticeable than the outer 2. Well also, when i turn the fuel screw all the way in on the middle it barely changes anything as well. The outer 2 carbs will almost make the motor die when the their fuel screws are turned in. Maybe the middle carb is having a partial blockage fuel issue and not making much power and as the engine warms it just becomes more apparent. Do you think the middle Fuel screw should change the motor rpm the same as the outer 2 when turned completely in?
 
Was thinking of my middle carb theory and saw these two areas that i didn’t reallly touch during the cleaning .
 

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i’m ordering a used tested exciter coil. This guy has my exact symptoms. My gut told me to replace it when i replaced the flywheel. 25$ gamble again. 50$ in now with the pulser coil. not bad. Gonna get this! will keep posted
 

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Ok i have a exciter coil and set of coils/plug wires coming all mint and tested with warranty for 80$. So i’m 100$ in and will have all major ignition components replaced except CDI. This should be a big leap forward. If this doesn’t work i will have to look at connections/grounds and the CDI more intensively. I can’t see carbs starting off running great then fall out 10 minutes later repeatedly. Two concerns- How reliable are these diaphragm fuel pumps? Should i throw a new one on just for peace of mind the old one looks peeling and old? I have pumped the bulb exceedingly during rough running with no change so does this 100% rule out fuel problems? Also- The top cylinder being 180-185 around water jacket/plug area vs the 2 lower being like 160-165. Is this a problem? Or does the heat just rise and this is normal I have a new anode and water jacket gasket but i see horror stories and can see buildup on the edge of the water jacket cover. I know it’s gonna be a mess and the bolts will be VERY hard to get out. Should i go ahead and open it up and clean it out? My boat pees great and never overheats but i’m concerned the top passage is heavily clogged. I do have a bolt-buster induction. bolt heater that may be able to get the bolts out without snapping them. Thanks
 
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