Hello I recently bought a 1989 Evinrude Junior 1.2 hp and I noticed that I am leaking oil from the lower unit, but to be more specific it seems to be coming from the gearcase head bushing assembly so I would assume its the o-ring that is the problem. Just to be safe I ordered all new seals which I will install upon their arrival. However I can't seem to find any information on the type or quantity of oil that I need to replace for the gearcase. I don't have the owners manual so I was hoping someone here would know. I appreciate any help on this matter. Thanks