How do you know it's blowing oil from the vent?The oil breather pipe should run into the Air-box.
You can download a manual from here.
http://trainwiththom.com/2009/02/10...00-or-cx500-service-or-parts-manual-download/
You can download a manual from here.
http://trainwiththom.com/2009/02/10...00-or-cx500-service-or-parts-manual-download/