OCD, I run the epic with your tidy bilge set up wired to the ebox without issues as well. Most of the time the bilge is off as the scupper handles the water evacuation, but often I run the bilge for a little while riding to check my if scupper hung open, still no running issues...
I've had some slight kick back on cranking too but it's funny you mentioned run backwards, I've seen what I thought was engine running backwards too. Ive had a lean misfire in hot summer weather cause it I believe, went away after low and high speed adjustment.
Then recently I switched to a lay down pipe with the water box real low and I confirmed water back flow into the engine at certain times while re-boarding or loading ski on the trailer.
On my set up wake approach going slow, after I popped the nose and let off the gas bringing nose down, then full throttle it would happen, about toss me over the bars. It seemed to be running on one cylinder and/or backwards and I'd have to kill the engine and restart it.
Mixture adjustment did nothing this time so I wondered if it was more back flow issue, "water extinguishing the spark in the rear cylinder", (my stinger was below the outside lake water level) so I had water in the pipe or at the stinger waiting to come in.
I raised the water box 3 inches and no more issue so far.
I thought it might be the epic too, did you guys get your buds figured out ? Sounds like it was the epic in your case ?
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