Ryobi String Trimmer Troubleshooting

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Troubleshooting your Ryobi string trimmer before taking it to a technician may save you time and repair costs. The company makes both gas and electric string trimmers, but the basic problem-solving steps are the same. Keying in on your trimmer's main functions can help you diagnose potential issues and determine if a service center visit is needed. Some minor problems may be handled easily at home.


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Eliminating Power Problems

If your string trimmer fails to start, check the spark plug first. Remove the plug, then reattach the spark plug cap, and lay the plug on the metal cylinder. Pull the starter rope and watch for a spark at the plug tip. If there is none, your trimmer needs a new spark plug. Replace the plug and retest the spark.


If the spark works but the trimmer still won't start, ensure your engine is receiving fuel. Push the primer bulb until it fills with fuel. If it doesn't fill, the primary fuel delivery system is blocked and a technician is needed. If the bulb fills but the engine won't start, your engine may be flooded. Take care to not push the bulb too many times or to start the trimmer with the choke in the "run" position, or you can accidentally flood the engine while trying to fix a different power issue altogether.


Clearing a flooded engine is relatively easy but sometimes messy. The spark plug must be removed and dried and the excess fuel must be purged from the motor. This is usually accomplished by pressing the throttle trigger while pulling the start cord. Refer to the owner's manual for your Ryobi model for specific instructions on clearing a flooded engine.


Investigating Engine Issues

If your string trimmer's engine starts but won't accelerate, make sure you allow the engine to warm up completely. This should take about three minutes. If it still does not accelerate, contact a service center. If the engine starts, but only runs at high speed at half choke, your carburetor needs to be adjusted. Ryobi recommends a technician to handle this job.


If the engine doesn't reach full speed and emits excessive smoke, check the oil-fuel mixture. Ryobi requires a two-cycle oil mix. Fill your trimmer with fresh fuel and the correct mix. Check the air filter and clean it, if needed. If the spark arrestor screen is dirty, allow a technician to clean it and investigate why.

Correcting String Concerns

If your trimmer's string won't advance when using Ryobi's EZ Line tap advance system, check to be sure it's not out of string. Replace the empty string spool with a new one, if needed. If string is on the spool, it may have welded to itself. Lubricate the string with silicone spray and it should release.

The string may also be worn too short or tangled on the spool. If so, try pulling the strings while alternating between pressing down on the spool retainer and then releasing it, until the string is freed. If none of these actions solves your problem, your engine speed may be too slow. Advance the string at full throttle instead.