45 hp Mariner, oil under engine cover

[perdidojoe]

I just bought an 86 45 hp Mariner, After 6/7 hours running I saw oil running down the side of it, opened it up and there is oil on the front of the engine.<br />I don't know if it's supposed to have an oiling system or not. Is it?<br />The previous owner said to mix 2 cycle oil 50:1. That's what I did with 87 octane gas, runs great but it does smoke a little.<br />I think it is oil as it doesn't smell like gear lubricant.<br />What are the best spark plugs for this?<br />What octane gas should I use?<br />Thanks <br />Pensacola