Guys, I know most of you don't like the Ryobi products but I have a question for you. A little over two years ago I bought a Troy-bilt (built by Ryobi) 4 cycle trimmer that was attachment compatible. Over the last couple of years I have amassed a few attachments for it. I have the pole saw (which works great), the tiller attachment (which is great for annual beds), the vacuum/blower attachment and no the articulating hedge trimmer (haven't had the chance to use it yet since trimmer died the day I bought it). I was using the trimmer the other day and it slowly died on me, like it was out of gas. It was low on fuel so I filled the tank and it would not start again. To make a long story short, I have rebuilt the carb, put a new spark plug in, checked for fire, checked the fuel filter and made sure the valves are adjusted right. All to no avail, it would not start. Last night I drained the oil, it was extremely runny (not viscous) and smelled of gas. I'm assuming that the rings are bad on the piston. Any other thoughts? Obviously if this is the case it is not worth rebuilding. I would love to move up to a commercial power head for my attachments, is there anyone else's power head that will interchange with the Ryobi trimmer plus attachments? Or maybe some one makes an adapter to goes between them. Right now I have almost $400 in attachments and moving to different brand that doesn't interchange would not be wise. If I were using this to make a living then it would make sense. If I go back with another Ryobi I will probably go for a 2 cycle. Is there any sort of "breaking in" of a new 2 cycle engine that would help it last longer? Any special oil or treatment that prolongs the engines life? (I know that is a loaded question).