Manually advance the line from the bump feed string head if bumping the head several times firmly against the ground does not advance the line far enough to meet the cut off blade. Turn off the engine, detach the spark plug wire, then push down on the spool while pulling on the line to manually advance the line. The line should advance with each ground strike; however, if the line is too short or the spool is loaded with less than 10 feet of line, the line may not advance correctly. Replace the line if it becomes fused. Rewind the line onto the spool if it becomes tangled. Use only the recommended size line for your model.
Turn the idle speed screw counterclockwise to stop movement of the cutting attachment when the strimmer is idling. This solution is also useful to reduce the RPM of the machine and to correct an engine that will not idle, but otherwise functions properly. Contact a service dealer for repair of the unit if adjusting the screw fails to correct the problem. The company warns against using a strimmer if the cutting attachment moves when the unit is idling.
Replace the fuel cap if you experience poor engine performance. Test whether the cap needs replacing by loosening the cap while the strimmer is running. If the machine’s performance improves, there may be a problem with the cap’s filter or check valve. Replace the cap itself, rather than cleaning the fuel filter, as the filter and check valve are an integral part of the cap and cannot be changed or serviced individually.
Store your strimmer in a vertical position. This prevents the engine from hydraulically locking, a condition where the starter rope does not move due to engine oil migrating into the combustion chamber. Place the unit on a flat surface in the upright position if the engine locks. This permits the oil to drain back into its reservoir, freeing the mechanism. Follow up by removing the spark plug, draining the plug hole of any accumulated oil, cleaning and reinstalling the spark plug.