Outdoor Power Equipment and Small Engines - Craftsman 6.5 HP loses power and stops

Hi,
I am a total newbie to lawn maintenance and repairs. So forgive me if I ask really dumb questions. I have a Craftsman 6.5 HP Briggs & Stratton lawn mower. I recently changed oil and I poured in more than I should have. When I started it up, there was a lot of smoke and there was also oil dripping. So I poured out half the oil and continued operating it. There was still smoke coming out and a little bit of leakage. The next week, my lawn mower seemed to have lost power and now when I start it, it starts but it keeps losing power and then it stops. One mistake I did was use generic oil SAE 30 bought from OReilly auto parts instead of the Sears Craftsman oil. Now I have emptied the OReilly oil out of the lawn mower and poured in the Craftsman SAE 30 oil but the problem still exists. Can anybody help?

Thanks.

The oil you had wasn't a mistake. You can use any decent 30wt oil. Check your air filter, I'll bet it's soaked with oil and the reason the engine won't stay running.

Hi Cheese,
Thanks for the quick reply. I'll check it out this evening and let you know if indeed that is the problem. Appreciate it.

Yes, it wasn't the oil..... sears doesn't make they're oil.... OReilly's doesn't make there's..... a major name brand company does, keep the small 18 ounce bottle of oil, and fill it with any name brand oil (be it quaker state, pennzoil, castrol, or havoline, etc.) and use that 18 ounce bottle to pour it in the engine..... no need to measure anymore. And cheese is right, the airfilter is more then likely covered in oil.... do not try and clean it, replace it... it basically when they get clogged... choke the engine and make em run rough..... no need to go to sears either, wal-mart, lowes, homedepot.... these places sells minor parts like filters.

Thanks a lot, guys. It was the air filter. It was all soaked up. I got that replaced and my lawn mower is just doing fine now...