longdistancerider· Premium Member
From the location and amount I'm going to guess that the oil pressure sender unit is leaking. The cover at the left top (looking at it) of the cooler is held on by the 2 of 6 bolts that holder the cooler. Remove those 2 bolts and the cover, re-install the bolts and after cleaning the area completely start the engine and watch it. You can throw a handful of baby powder on the area and where ever the leak is will turn into a gooey mess. If it's the sender then remove the wire from it, 7mm wrench, and unscrew it to replace with a new one. I'm hoping it's the switch because the O-ring that seals the cooler to the lower case hasn't been available for a couple of years now.