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Ron, if you have fire to the plugs with the knob switched to battery, then your commutator is OK. You won't have voltage to the coil unless the engine is turning. Henry Ford's magneto is merely a crude AC alternator that only produces voltage when the magnets on the flywheel are passing by the pickup coils at the back of the crankcase. Now, if your engine has worn thrust bearing surfaces (most do), there will be too much air gap between the magnets and coils to get fire at hand cranking speed. To get around this problem on my '23 Fordson I have knife switches to switch from the battery to the magneto once the engine is running. I suggest you try to get it to start and run on the battery first. If the engine won't start with fuel and spark then you most likely have wires crossed between the commutator and the coils. The firing order is 1,2,4,3. The easiest way for me to find out which coil buzzes at #1 TDC is to remove all the plugs except #1 and crank it over carefully by hand with the battery disconnected. You will then know for certain when the #1 piston reaches the compression stroke. Switch to battery and then you will know which coil is being grounded to the commutator by the buzzing sound. It should be the coil closest to the radiator. If the properly wired/timed engine will run on the battery (positive ground) then die when you switch to the magneto, you probably have a bad connection in the magneto circuit. Take the terminal plug from the side of the block and check the end of the probe for rust and lightly sand it clean. There is no lead connected to it on the inside so don't worry about breaking an old rotten wire. Check also the point of contact in the hole you just took the terminal plug from. Replace the plug and check all connections to it including the switch contacts. To prove the output of the magneto, with the engine running put a volt-ohm meter (VOM) set on AC volts on the terminal plug. If there is no voltage present with the engine running, remove the external wire at the plug and read again. If still no voltage, your problem is in the magneto. Sorry for such a long post but I hope it gives you an idea of several things to check. Oh, one more thing you can do to check the coil connections and isolate commutator problems is to jump a wire from the block casting (ground) to the top terminals of the coil box. With the battery switched on, each coil should buzz in turn. Safety note: When you bypass the commutator you can get a backfire in any cylinder - especially if you have just been cranking the engine to start it. Any gasoline vapors in the cylinder can ignite with or without compression.
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