Small Engines (Lawn Mowers, etc.): Oil seal leak

Question
Kawasaki mod.757 25 hp. gas ............
Replaced crankcase oil seal but still leaks.
Is this because the crankcase doesn't have a return or drain - oil port behind the seal?
So the oil under pressure has no place to go.
Other 757 have this problem, ..... are you aware of this?

The seals are in good shape and so is the shaft.
The oil has to be under pressure for it to be able to come out that fast.

Answer
If oil is coming out that fact I would perform a crankcase vacuum check.  The crankcase should have a breather that allows internal pressure to vent out of the crankcase. This is a one-way pressure vent and the breather prevent atmospheric pressure from entering thus allowing the engine to generate a vacuum to keep the oil inside the crankcase.

I have not heard of this problem.  Are there any message boards discussing the issue?

Do you have a vacuum/pressure gauge or a manometer to check for crankcase vacuum or pressure?

Eric