If it does NOT need the choke to start, I would be suspicious of the carb. It sounds like it is flooding way too easily. When these engines are flooded they are not easy to pull the flood through, but just go away for a day or 2. When I flood my 300U, I have to pull the spark plugs and heat the electrode end with the burnzomatic torch and crank the engine around a few times without the plugs in to ventilate the cylinders. Then it is like starting "fresh". Do you have ethanol gas mix (10%) in the fuel tank? That stuff will draw water vapor from the air and not want to fire at all. I have had that problem....looks like gas, smells sorta like gas, but doesn't fire. If that is the problem, it can be started with ether and then will run on the crappy gas mix. Some years ago, I 12 volted my 300 and it has become about 100 times more reliable. In super cold weather with no heater, it seems that the valves may be moving too slowly in their bores and all sorts of strange things happen, but starting is NOT one of them. I have had this problem in sub zero temps, but only on 1 or maybe 2 cylinders. I find that to be a mystery. Good Luck with your challenge. Paul in MN
|