You might also check to make sure your power take off isn't engaged. They won't start if it's engaged. On my John Deere you also have to push on the brake or it won't turn over.

With that much gas coming out, I would suspect that your float is out of adjustment. The float is what regulates your needle valve and if it is set too high, excess gas will flow into your carb. However, this is at times evident when it is not running. It just pours out your carb. If it is running rich, that's a problem with your air/gas mixture and will cause smoke. Check your settings. Try spraying some WD-40 around your carb while it is running to see if your carb has an air leak. This will make your engine speed up or down. My bet would be the carb settings. Good luck!

I'd suspect either too much air gap on the clutch or not enough amps(not volts) to the clutch coil. The air gap can increase with wear, not positive what yours calls for but 10 to 15 thousnadths should work fine. If it's an amperage loss due to age and resistance build up of the clutch coil and/or wiring&switchs, a 30 amp constant duty relay installed correctly will cure that. The relays are readily available at any auto parts store, cars and trucks use them for fuel pumps, fans, and AC clutchs which are basically the same as the electric PTO. I installed one for the lights and one for the PTO clutch on my 1855MF and 1650MF. Mine are wired like a lot of lawn and garden tractors in that everything goes through the ignition switch. When running with the lights and pto on the ignition switch would get hot, the relays cured that.

Does anyone out there have a John Deere L120 have a issue with the following it has a extra regulator box on side to keep battery charged while the electric PTO is working also need to know or would like a pic of how it is wired it shows voltage on the regulator when switch is off if anyone can help with pic of how theiers is wired or info would be greatly appreciative.