I got mine working, its a Ryobi RCT2800AD. The spark arrestor (location in the manual) was clogged so I pulled it out, could not find a replacement but works fine without it. While the covers were off I cleaned the whole engine with degreaser, rinsed and dried it out. I also washed the air filter with soap, dried it and poured a little oil onto it as recommended in the manual. I screwed up the idle screw (clockwise) a few turns, put all the covers on, then followed the starting procedure. Prime the fuel by pressing the priming bulb a few times till you see sufficient fuel running through the lines. Put the choke lever in position 1 and pull the starter cord 5-10 times (throttle trigger fully in). Put the choke lever in position 2 and pull starter cord (don't forget to hold throttle trigger fully in), it should start. Hold throttle in for 30 sec to 1 min till the machine warms up then put the choke lever in position 3. Cut your grass.
I had to replace the fuel lines later as they had gone soft and started leaking. It doesn't idle without the cutting line turning, as I adjusted the idle screw it konked out so had to leave it idling high. Otherwise it works well, even without the spark arrestor. I can't remember where I downloaded the manual but it is on the internet somewhere, search specifically for ryobi rct2800ad manual.
Good Luck.
Lionel.
December 2010
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