Ok don't know alot about this Ski. Was brought to me to look at. I know it was submerged. Don't know much more then that. Length, how much? nothing. Ran some checks and found wasn't getting power to the coil. Bought a used Known to be working Box. Complete with coil, regulator, CDI, etc.. Exchanged boxes and running tests still weak to no spark condition. Only got about 3.5 VDC from box to coil. Don't have a manual just looking for ideas. Is there a master on/off switch for these? Cranks strong

 

I'm pretty weak with electrical issues, wish I could help you.
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