Evinrude LightFour 4383 Spark Issue

[4383]

Hello,
Got a mid-late 40s LightFour that currently has spark on 3 of 4 cylinders. One of the coils had one of the plug wire connections repaired in the past, and that wire has no spark (probably why we found the motor out in the woods in a box buried under a bunch of junk!). Anyways, points are good/clean and plug wires are new, also the suspect coil has continuity across the leads (7.5 Ohms, other coil is 8.0). The other side of the coil puts out a nice spark, but the trouble side did not consistently, and now we can’t get a spark out of it at all. Just wondering if anyone has any insight into this besides the obvious (bad coil), or if anyone might have a working coil they are willing to part with. I’ll probably post a WTB in the classifieds as there are currently none for sale there.

[mercuryman]

I have seen that happen also it has to be the coil. There must be a short to ground inside so one side will fire on one side.

[garry-in-michigan]

That same coil was used in the post war (WW2) Zephyr. Try Doug Penn for a good used coil. . . 😀

[4383]

Thanks for the reply! I’ll give him a try.

[2fast4me]

4383, you may have one spark plug lead that is arcing to ground at the armature plate, lots of flexing in that area, coil might be fine.

2Fast4Me

[4383]

quote 2Fast4Me:

4383, you may have one spark plug lead that is arcing to ground at the armature plate, lots of flexing in that area, coil might be fine.

That was a possibility which is why it now has new plug wires, as well as insulation over the soldered leads on top of the coil.

[joecb]

4383, so did the new wires solve the problem? If you are getting spark from one side of the coil and not the other there HAS TO BE a connection to ground somewhere on the side that is not showing a spark.
Joe B

[4383]

quote JoeCB:

4383, so did the new wires solve the problem? If you are getting spark from one side of the coil and not the other there HAS TO BE a connection to ground somewhere on the side that is not showing a spark.
Joe B

Negative, no spark from that wire, before or after replacement. New wire is not grounded anywhere, so my money is on the coil being grounded internally.

[2fast4me]

4383, high voltage can be funny stuff. The next step is to substitute a know good coil unless others have better ideas. Oh by the way are You measuring any resistance to ground on the spark plug wires.
Jim

2Fast4Me

[2fast4me]

Sorry, I just reread your last post, time for a coil. Jim

2Fast4Me

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