Has anyone ever spun their crankshaft side coupling loose in the water?

I was trouble shooting some carb issues on the trailer in the water, and may have got carried away revving engine/loading ski up. I solved my carb issues (pinched pulse line), but halfway through my actual run that day the ski would only "slip" above 10mph or so. Limped the ski back to the dock. Traction below 10 mph is fine.

Once could theoretically spin the crankshaft side coupler loose if it is a regular thread - correct? The driveshaft side coupler would only spin itself tighter.

Already pulled the pump - impeller/driveshaft splines are fine. Motor is almost out of ski, but I figured Id post for some tips.

Stumped and tryinna ski!

Thanks for any insight.

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