Snorkel Man Lift, no start

I've got a Snorkel man lift with a Ford LRG-425i Engine, and when the weather is warm is seems to start and run fine. but now in the winter it won't start for anything, I was able to get it to start a few times by taking the coil out and putting it in the oven for 15 mins and then it would start with a shot of ether. so got a new coil and still same problem, also when it's cold there is no spark at all. sometimes when I have one of the plug wires off checking for spark I'll get 1 spark and hear the engine try to start but since I have the wire off it won't start, and then it goes back to no spark. any suggestions?

Snorkel Man Lift, no start