How to Troubleshoot a Yard Machine Grass Trimmer
- 1). Check the fuel tank if your Yard Machines grass trimmer fails to start. If the tank appears low, fill it with a mixture of gas and 2-cycle engine oil. Use 8 ounces of oil for every 2 gallons of gas. Press the primer 10 times. If you press the primer too many times, the engine floods. When this happens, squeeze the trigger while you pull the start cord.
- 2). Check both the air filter and the spark plug if the engine still does not start. If either part appears dirty or damaged, replace it. To remove the spark plug, pull the wire off its end and unscrew it with a 5/8-inch socket wrench. To remove the air filter, move the choke to partial choke and remove the four screws securing the cover in place. Lift the air filter out. Clean or replace it.
- 3). Adjust the carburetor if the engine starts but will not idle. Let the Yard Machines grass trimmer run for two to three minutes. Insert a small Phillips screwdriver into the screw hole located beneath the choke. Turn the screwdriver to the left or right until the grass trimmer idles successfully.
- 4). Clean dirt and grass off the trimmer, with a damp cloth, if the engine fails to accelerate but has properly mixed fuel and a clean air filter. A clogged trimmer head also prevents the trim line from advancing correctly.
- 5). Refill the spool line when the string gets low and fails to advance. To remove the spool, unscrew the bump knob and pull it off the grass trimmer. Pull the outer spool off the trimmer and remove the inner spool. Wrap new string around the inner spool. Do not overfill the spool, and make sure the string does not twist. Extend the string 4 inches out the outer spool's side holes.
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