Ryobi makes a good trimmer for the average homeowner. The components are good quality, and with the right maintenance plan, these tools will last a good, long while. And they will run well, too. The key to adding years to the useful life of a yard tool, like a trimmer, is to maintain the tool regularly and properly. Most maintenance tasks do not require a mechanic's knowledge to complete. These tasks are simple and common sense. When a maintenance schedule breaks down, so will the trimmer; and that is when troubleshooting is required.
There are many causes behind trimming issues, but they are easy to troubleshoot. If the bump-feed trimmer head will not allow trimmer line to advance, one of five issues is present: the trimmer line has been welded to itself; the amount of line on the spool is too short to advance effectively; the trimmer line was allowed to wear too short; the string is tangled inside the spool (this is a very common problem); or the engine speed is too slow and must be increased by throttling the engine up to full throttle. The cause of the first four issues will not be obvious at first. Decrease the throttle and shut the engine off. Remove the bump-feed trimmer head and free the trimmer line from itself; add new trimmer line to the spool; pull on the trimmer line while pushing on the bump feed button; or remove the spool and untangle the trimmer line.
The most common problem with Ryobi trimmers is that the engine becomes progressively more difficult to start. There are three possible scenarios that are causing this problem. The first is that there may not be any spark to ignite the air/fuel mixture. The best way to find out is to take the spark plug out of the engine and check its condition. Disconnect the spark plug wire and remove the spark plug with a spark plug removal tool. Sometimes the spark plug is just dirty---fouled by carbon build-up. Wipe the fouling off of the plug with a clean cloth rag or paper towel and inspect the plug for damage or wear. If the plug is damaged or worn, replace it with a new spark plug and reconnect the wire before attempting to start the engine again. The second problem may be that no fuel is reaching the combustion chamber. Check the fuel tank to see if it is empty first and fill it with fresh fuel that has been mixed with the correct amount of 2-cycle oil (50:1 ratio). After filling the tank fully depress the primer bulb three times. If it does not fill with fuel, the tube is clogged with debris and must be cleared. Ideally, this should be done by a qualified service dealer. But if you would like to do it yourself, drain the fuel tank, remove it, and clear the blockage from the fuel line. The third problem may be that the engine is simply flooded with fuel. In severe cases, remove the spark plug and point the spark plug hole toward the ground while repeatedly pulling on the starter cable (10 to 15 times). Replace the spark plug and attempt to start the engine normally. In less severe cases, setting the START lever to the start position and repeatedly pulling on the starter cable should yield results.