The Ryobi machines have a very weak spark, it makes it hard to get them to run at the best of times. I have been restoring or (cleaning) an old japanese machine that flashes blue spark in full sunlight! I suspect it is a Tanaka, 20 years old. It may be worth removing the carby, remove the rubber type parts and soak it in metho overnight to remove varnish build up etc. Clean the whole machine as best as you can. Just cleaning around the magneto can make a big difference to reduce power leakages. The most common problem with those machines is the pop off pressure, but when you have it going you need to have a screwdriver ready to make quick adjustments, it is good to have a friend nearby. Remove the cutting head to reduce load as the clutch kicks in. Tune it again later under load, and after warm up. With this sort of gear you have to do your own servicing to make it worthwhile. Cheers.
