sx550 runs out of water does once in water and no power

I have a fully rebuilt sx550 with a new mikuni 46 carb, rebuilt stator and ebox. My original issue was it ran outside of the water but as soon as it has a load and is in the water all power is lost and it does. So i got my electrical system rebuilt and tested it today and i have the same issue and it also tried to runaway on me outside of the water and had to pull the plugs. Wondering if i might have an intake leak or what other things should i check??
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
Jetted wrong, exhaust leak or bad reeds will all give these symptoms , did you check for the proper jetting or just bolt the carb on and hope for the best ?
Regrettably there hasn't been much of any posted info about running a 46 on that engine, on a 44 I would say 100-110 pilot. 130-140 main 2.0 needle and 80 gram spring , 20-22 popoff pressure , jetting on the 46 won't be exactly the same but that should put you somewgere in the ballpark.
 
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Myself

manic mechanic
Location
Twin Lakes AR
One of the first things I check on an old KAwi doing this is the fuel pickup assembly. They are bad to crack at the top and suck air. Pull it out, plug the low ends, submerse in a bucket of water and blow through the pickups.....look for air bubbles to blow out. This is actually fairly common.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
I had this issue as well, what it ended up being was an exhaust restriction, the short hose from the pipe to the waterbox had delaminated inside, the outside look perfect, when I took it off you couldn't even see daylight through the hose, replaced the hose and it ran like a raped ape.
 
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