Originally Posted by
DOCDRS
I totally agree less with boat listing, but the height of water in the area directly above the hinge is what determines the force( in all directions ) at the hinge or along the floor / engine wall. there is no reduction due to an apparent leaning of the bag. Yes the more the boat leans the less the force, but when compare a 400 lb bag to an 1100 bag the force exerted on the vall at the area of the hinge and thus the entire area of the wall is 66% greater. That is assuming that the bag is not overfilled at all.
The pressure at the hinge area is .577 lbs per square inch vs .866. Less (but still proportional) to any listing of the boat. If there is any expansion of the bag upwards , due to excessive filling then the force will be great increased depending on the pressure that the filling pump can exert. I think this is where one can increase the force imensely on the engine wall.
Plus this force will be increased if a cork :) is used to prevent bag emptying , or if the discharge/vent line is on the opposite side of the boat.
so if we take a 36x24 engine wall the amount of force is equivalent to about 378 lbs sitting on it 1100 lb sac , vs 166 lbs for the 400lb sac. A considerable difference!!!.....but that is level a 10 degree list would result in 10% less weight.... roughly :)
the bag deforms but that has nothing to do with water pressure and pressures exerted