CD-13 ignition arc

[joshadurham]

Got my CD-13 all back together today with all new points, condensers, plug wires, and coils. it started right up, but pretty wuickly began arcing inside the magneto. I took the flywheel off and found one of the green wires from one of the coils had been rubbed a bit, and some bare wire was exposed. I put some shrink wrap over the bare wire and tucked it back under the coil away from anything moving better. assembled and fired it up, and it still arced. I can hear it arc, and it misses every time it arcs, and wont run good at all. Did I put something back together wrong? will it still arc through the shrink wrap?

[chris-p]

Run her at night to determine where the arc is coming from? Maybe a plug wire as well.

[joshadurham]

Yea I guess nothing is impossible. But the plug wires are brand new.

[fleetwin]

Yeah, sure sounds like a plug wire/coil is arcing to the plate. Run the engine at night, maybe you will be able to see the arcing if it is occurring on the bottom of the mag plate.

[joshadurham]

would that bare rubbed green wire from the coil keep arcing through my shrink wrap, or is it probably arcing somewhere else as well?

[chinewalker]

Did you install the rubber sleeves where the plug wires enter the coils? Are you using solid core wires?

[joshadurham]

Yes on the sleeves, and I got the plug wire from antique outboard. Solid core with new plug boots.

[joshadurham]

Test ran it tonight. Still arcing and missing every time it arcs, but never saw a spark in the dark at any point on the plug wires. I can hear it in the magneto. I pulled the flywheel and everything looked normal.

[Doug Wilson]

might double check all the connections including the spark plug wires. Also check the points and see if they look burned could be even with new condensers could be one of them is bad and the arc is the points opening.

Doug

how is it motors multiply when the garage lights get
turned off?

[Mumbles]

What brand of coils did you install? The green German Prufrex and black OMC/BRP ones are pretty much bullet proof but there are questionable Asian made knock-offs on the market now.

If your wiring is good, remove the coils again and look at the bottom of them. An audible high voltage leak will leave a small black mark about the size of a pin head. Even though the coils are new, the insulation may be faulty.

To firmly connect the spark plug wires to the OMC/BRP coils, they push straight in. A little bit of silicone spray (rubber lubricant) helps them slide in. The pin on the Prufrex coils is usually threaded and the wires have to be screwed in.

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