1941 h revisited from last week

Ok so I recleaned the carb on this h for the 3rd time, it has a freshly rebuilt mag,new plugs and wires,clean fuel bowl and line. It still will only run when on choke and it gets very hot around the manifold... my question is could the baffle in the distillate manifold be in the distillate position and could that be causing it not to run properly on gas thanks jim.

Can you open the load screw up & make it smoke black? If not you still have something plugged in the carb. Those cast iron carbs rust shut & have to be cleaned with drill bits.

(quoted from post at 17:46:48 05/15/12) Ok so I recleaned the carb on this h for the 3rd time, it has a freshly rebuilt mag,new plugs and wires,clean fuel bowl and line. It still will only run when on choke and it gets very hot around the manifold... my question is could the baffle in the distillate manifold be in the distillate position and could that be causing it not to run properly on gas thanks jim.

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Are you sure that freshly rebuilt magneto is timed correctly?

Yes the mag is in time we marked it when disassembled and timed it prior to rebuilding the carb

It's not drawing enough fuel for some reason. That flapper in the manifold just makes it run hotter to atomize the distillate properly. If it atomized the gasoline too much, it would run great just be down on power, but get the best fuel consumption you ever saw! If you still have the other manifold, and it is in running condition, it would be a quick 15 minutes to install it and run the engine to see if that makes any difference.

Is the manifold itself stopped up or otherwise not allowing the engine to draw properly? What about the valves? Any sticking, etc?

When you say it will only run on choke, is that at idle or working speed? Can you spray ether into the intake tract and make it run with the choke off? That would narrow it down to a fuel delivery issue. When rebuilding the carb, did you run a drill bit through the jet to increase its size? What about the venturi, did you install a larger one or otherwise increase the size of it?

To expand on what rustyfarmall asked, did it run fine with the new magneto installed prior to the carb being removed the first time? And for that matter, did it run okay prior to this recent work being performed?

And to stick to the kiss principle, is the fuel tank cap's vent hole stopped up? I had my SM stop in the middle of a parade one time over that simple little issue. An old-timer there asked me what the last thing I changed was, I told him I had just put on a new fuel tank cap with a gauge in it. He said unseal it and try to start it. It opened with a very slight sucking sound, then she fired right back up. Later back at home, I took the cap apart and opened up the vent hole. Works fine now.