Thank you to all of you for the information. It will be very helpful! In fact I did what you guys said and changed my plug today with a OS #8 and the engine ran perfect. I am not sure what was in the engine before it was old looking though, should ask the previous owner. But I got the motor running really well and thas all that I wanted to do. Maybe down the road I will experiment with other plugs but for now it seems that the OS #8 does the trick for my OS 46 SF!!

Thanks again everyone,
Chris