How to Troubleshoot a Gas String Trimmer
- 1). Turn the switch on the gas string trimmer to "On" if the engine will not start. If this does not resolve the issue, turn the trimmer off and depress the primer bulb until it is full of fuel. If the bulb does not fill, the fuel delivery system is blocked; contact a service dealer for repair.
If the bulb does fill, the engine is likely flooded. Pull the spark plug out and turn the trimmer so that the spark plug hole faces the ground. Set the choke to "Run" and pull the starter cord 10 times to clear the fuel line. Replace the spark plug and pull the starter cord three times to start the engine. If it doesn't start, set the choke to "Full" to start. - 2). Fill the trimmer with fresh fuel and the specified oil mix if the engine will not operate at full speed and it emits smoke. Replace the air filter with a new filter as another way to try to resolve this issue. Lift off the air filter cover, remove the old filter, place a new filter in the old filter's spot and replace the air filter cover.
- 3). Spray silicone lubricant on the line if it will not advance. Advance the line at full throttle, remove the line from the spool and rewind and install more line to try to resolve this issue.
- 4). Run the trimmer at full throttle and cut the grass from the top down if grass wraps around the trimmer head.
- 5). Run the trimmer at full throttle, replace with fresh fuel and the correct oil mix and use a clean filter if you experience oil dripping from the muffler.
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