I have a 343, 2005. If I close all through hulls then no water. If I leave open the air conditioner through hole and run the air conditioner, salt water fills the bilge and it is coming from the two holes that are along side the engine mounts. The through hole is not leaking, the stuffing box is not leaking. The air conditioner lines do not appear to be leaking as the water is coming from under the stringer under the front engine mounts. As long as I don't turn on the air conditioner, I am okay. Driving me crazy.