When I put my boat in at the boat ramp and idle out past the no wake zone I put the throttle down and it comes out of the hole great and runs great across the lake. I stop the boat and fish awhile get ready to leave and when I put the throttle down it just boggs down like it is flooded. It does not die it is just like there is no power but after starting it and stopping it it will finally come out of the hole and run real good until I stop again. It also does this at the boat ramp when I am loading it. I will put it up on the trailer and then give it the throttle to move it the last little bit and have know power it just boggs down. I have 85-90 psi on every cylinder. What would cause this, is the back wash flooding out the motor?