Re: evinrude superfast twin leaks oil above cavitation plate
That hole is a drain hole for unburnt two-cycle oil/gas residue. That oil is not all burnt up by the engine and has to go somewhere. If you have gear oil leaking where the skeg attaches to the gearcase, you have to remove the lower unit and remove the bolts that hold the skeg on. Then replace the spaghetti seal and put some sealant on the whole seam before re-assembling.