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Seadoo Challenger Twin Motor Electrical Issues- Please Help!

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treetopflyer737

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I just did a complete restore on a 1997 Seadoo Challenger. Both 787 motors were rebuilt bottom end up, carbs were rebuilt with PO pressures set to 38psi, and countershaft and rotary valve timing was checked and double checked.. I took the family down to our lake for the weekend to take her on a break in run and am having some electrical issues.

Both motors start right up, however starboard motor is retarding itself at 3500 RPM and is showing its RPM on the Port Motor RPM Tach. Port Motor starts beautifully and revs to max rpm without a hitch however is not showing its RPM on either Tach.

I read some old threads on the nuetral switch going bad but wouldn't both motors be retarded to 3500rpm if this was the case? I took the throttle and shifting linkage out and only see one switch?

I did turn the motors a few times after accidently knocking the sparkplug caps off the grounding tabs. Is there any electrical parts that may have gone bad from sitting or from starting the motors without the spark plug caps grounded? I'm stumped. :facepalm: I also stepped on the H20 sensor mounted on the top of the head and broke off the connector on the starboard motor that is retarding itself at 3500rpm. Could this be causing it possibly?

I have my shop manual with me and all the tools I need to try things, please help- I would be forever grateful.
 
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Ended up starting to tear motor down to see if it was a rotary valve timing issue and noticed the rotary shaft has a bunch of play and that the timing "slipped" while cranking the motor over. Not sure what went wrong but need to yank the motor and check out the rotary shaft gear.
 
do the twin motor boats have two voltage regs/rectifiers? sounds like the infamous bad rectifier issue.
 
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