Weird Electrical Problem 1964 JW19A 3HP

[wtnordin]

This is driving me nuts. 1964 3HP JW19A. The problem is that the top cylinder is the only one that fires. Both coils check out OK. I have swapped coils, condensers, points, everything. It does not matter.

I am turning the flywheel by hand, and the top coil produces a great spark - no problem.

The bottom will not fire.

I have swapped out everything, sparkplugs, coils, points, condenser

I have wrapped both wires with tape - no difference.

It seems impossible. I can swap everything around and it makes no difference.

If I check the spark by placing a screwdriver in the spark plug boot and holding on to it and then turning the flywheel by hand, both wires seem the same to me - it will shock you quite well.

[F_R]

This is driving me nuts. 1964 3HP JW19A. The problem is that the top cylinder is the only one that fires. Both coils check out OK. I have swapped coils, condensers, points, everything. It does not matter.

I am turning the flywheel by hand, and the top coil produces a great spark - no problem.

The bottom will not fire.

I have swapped out everything, sparkplugs, coils, points, condenser

I have wrapped both wires with tape - no difference.

It seems impossible. I can swap everything around and it makes no difference.

If I check the spark by placing a screwdriver in the spark plug boot and holding on to it and then turning the flywheel by hand, both wires seem the same to me - it will shock you quite well.

So you did everything but replace the plug wires. (!!)
Are you sure you are setting the points right?

Gotta love your spark test. But you aren't going to catch me doing it that way. I hate being shocked!! That thing will put out several thousand volts.

[lindy46]

Yup, my money is on the plug wires.

[wtnordin]

Yup, my money is on the plug wires.

I have wrapped both plug wires with electrical tape. The points are dead on at .020. I can swap the coils, condensers, points, whatever - it does not make a difference.

[lindy46]

If wires are original, could have an internal fault. They should be replaced.

[wtnordin]

If wires are original, could have an internal fault. They should be replaced.

I will swap the wires and see what happens. Could be an internal break.
I bought some at the auto store, but they are just slightly too large to fit into the coil hole.

[14ftgrumman]

as long as you are in there, REPLACE plug wires and NEW spark plugs.
if it were mine, i'd replace everything. plugs, points, condensors,coils and plug wires.
i had the center contact (the pin in the coil that goes into the center of the plug wire that contacts the wire in the plug wire) rust off.
and you might get a real spark checking tool, and make sure that spark is what it should be.

[lindy46]

I will swap the wires and see what happens. Could be an internal break.
I bought some at the auto store, but they are just slightly too large to fit into the coil hole.

Get some copper core wires from a Johhnyrude dealer

[F_R]

Get some copper core wires from a Johhnyrude dealer

The carbon string wires made for cars won't work. You need 'wire" wires.

[wtnordin]

The carbon string wires made for cars won't work. You need 'wire" wires.

OK - I have read about the copper wires. But someone explain why the carbon wires for cars will not work. I am always open to learning about things.