The crankcase oil fills the pan and starts to drip after 5 to 10 hours of use.  I shut off the fuel when I am not using the tractor.  Basically, the tractor needs to be fixed.  

I have the service parts manual for the pump.  I do not see an O-ring that should leak fuel.  Is there some oil seal on the quill or gear case under the hydraulic head that can leak fuel down?

Can you provide some insight?

Thanks,