Oil leak FD501V engine

I have tried everything I can think of to stop the major oil leak on my 2003 John Deere LX279 lawn tractor.
The motor is a Kawasaki FD501V-CS04.
The clutch bolt came loose or broke off a few times over the past several years and I replaced it successfully.
But this last time I can not stop the oil from leaking out of the crankshaft seal area.
I replaced the bottom oil seal a few times first.
Than I replaced the bottom half of the engine with a brand new part as well as several new seals to no avail. (note: the bottom bearing on this engine is not replaceable requiring you to purchase a whole bottom end casting )
I checked the crankshaft rotation with a dial gauge and it is true.
Just visually lookin at the bottom of the engine It  seems as though the crankshaft is slightly off center with the engine some how making the seal also off center.
How can this be ?
This machine has only 345 hrs. on it.
Has anyone ever seen this phenomenon ?
Any help or suggestions will be appreciated.