Here is the problem why your battery failed:
A trickle charger can not/should not be used to maintain a battery over a long period of time. You need to get a battery maintainer.
Something like this...
Two cycle engines are very susceptible to atmospheric pressure, humidly, and outside air temperature changes.
So it is not unreasonable to expect that some adjustment of the carb may be necessary when there are large changes in the above.
Richard
It took me about an hour of searching the internet to finally figure out how that engine is suppose to work. And even the authors of the info I found were not completely sure of how it works. Plus it appears that Sthil has had trouble with their plastic cam gear.
Richard
I take it that the wheels that you have do not have bearings in them. Here is a part that appears to be compatible with your machine. Pricy but with bearings:
https://mowthelawn.com/products/john-deere-am148120?_pos=1&_sid=63a230cbe&_ss=r
Sounds like flooding to me. The typical way to clear a flooded engine is to crank the engine with the throttle wide open.
Next time this happens, crank the engine for a few moments, then pull the plugs, look and see if they are loaded up with fuel.
Richard
The sudden engine stop may have caused the cam timing to jump a tooth or two. I'm not failure with the 8N, but if it has a timing chain, it could be worn out and needs replacing.
Most fuel shut off solenoids have two coils, the pull-in coil and the hold coil. You need to apply voltage to the hold coil and then hit the pill-in coil with about 1 second of voltage.
Applying voltage to the pill-in coil a time longer than about 10 seconds will cause it to burn out. If you...