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-   -   911SC no spark (http://forums.pelicanparts.com/showthread.php?t=1181248)

RDM 08-15-2025 04:28 PM

So solid continuity for the coil connections all the way back to the 6-pin connector. A to A, 31a to negative both show zero ohms. Evidently the damaged insulation and potential contact between the conductors was not the problem.

ischmitz 08-15-2025 04:39 PM

Dru,

The primary voltage from the CDI to the coil is up to 450V. At that level you might get arcing between the exposed conductors. A simple ohm meter reading won’t identify this.

RDM 08-15-2025 07:11 PM

No exposed conductors at this point.

Jonny H 08-15-2025 10:18 PM

Quote:

Originally Posted by ischmitz (Post 12516729)
Dru,

The primary voltage from the CDI to the coil is up to 450V. At that level you might get arcing between the exposed conductors. A simple ohm meter reading won’t identify this.


Agree, with the break in the coil wire insulation, the HV may well arc to ground ( e.g. any part of the engine metal or even the coil casing), rather than going through the coil. That could well have damaged the output stage of the electronics.

Since you are a few miles away, I can share what to look for through our support so we can get this fixed for you.

RDM 08-16-2025 11:17 AM

Sometimes it take a while to remember things. Like the spare coil and CDI stashed in the smuggler's box just in case back when I had intermittent spark failure.

http://forums.pelicanparts.com/uploa...1755371575.jpg

And what do you know, it's a Bob Ashlock inspected (in 2013!) unit.

http://forums.pelicanparts.com/uploa...1755371575.jpg

Plug it in, and...

http://forums.pelicanparts.com/uploa...1755371575.jpg

So now on to the repair process for my broken parts.

Thank you all for your help. I am now goin' mobile!

mysocal911 08-16-2025 01:02 PM

Since your spare CDI is a 6 pin and has not been rebuilt, it should be!
The 6 pin has a much higher failure rate than the 3 pin, because of a key component.
Using it as a spare is risky, even though it runs the engine now.



http://forums.pelicanparts.com/uploa...1755378065.jpg


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