Distributer Mounting seal question

[Noah H]

On my d34 230 my underneath my disturber is leaking pretty bad when running. I am going to put an o ring over the base of the shaft but there is a small hole underneath in where the distributer mounts on the block. Maybe an oil return? Not sure.  
 

will an o ring block that hole? 
 

thanks. 
 

 

[JBNeal]

additional information - distributor mounting gasket