XLT crankcase filling with gas

I have a 1997 Polaris XLT Limited and the case fills with gas overnight. I have replaced needle and seats and o ring. I also replaced fuel pump diaphragm and gaskets thinking it was coming from pulse line. When I first picked up the sled it had been sitting outside for two years and had water in the tank (that I didn't know about at the time) which caused a bog that I couldn't fix so I had to bring it to a shop where the tank was drained and carbs got tuned up. Since there was water in the tank I assumed the fuel pump diaphragm cracked from water in the gas freezing and expanding. It does look like the gas is coming from carbs into the cylinders but I just can't understand why since the needles and seats were replaced. The N and S cut off the fuel when I pour it in on the bench but once there in the sled they leak. Sled is level.

Does anyone have an answer for this?
Thanks, Erik

XLT crankcase filling with gas