Gas Line Trimmer: Won't start
The engine needs gas, compression and spark in order to start. First, make sure there's fresh gas in the tank-old gas accumulates water and burns poorly. Replace the fuel if it's old. Add fuel stabilizer to the gas when you refill the tank to help keep the fuel fresh.
If the fuel is fresh, check the fuel lines for cracks. Air enters the carburetor instead of fuel when the fuel lines have cracks. Replace the fuel lines if you find cracks in the lines. If the fuel lines are okay, you may need to rebuild or replace the carburetor because a dirty carburetor won't supply the engine with fuel.
Next, disconnect the spark plug wire and remove the spark plug. If you see deposits or corrosion on the electrodes, replace the spark plug.
Finally, to check for compression, remove the spark plug, press your thumb over the opening and pull the starter cord. If you don't feel air pushing from the cylinder, it's likely that the piston rings need to be replaced (for an accurate compression reading, use a compression gauge).
Rebuild the grass line trimmer carburetor
Rebuild kits are available for most carburetors. The kit contains essential components for rebuilding a carburetor, such as diaphragms, seals and gaskets. You can sometimes fix a fuel supply problem by dismantling and cleaning a carburetor. Use the kit to rebuild the carburetor after cleaning it.
Replace the grass line trimmer carburetor
The carburetor mixes air and gasoline in the proper proportions to create a combustible gas. If the engine starts and then sputters, or doesn't start at all due to lack of fuel, you might need to replace carburetor. It's often more cost effective and practical to replace the carburetor rather than rebuild it.
Replace the grass line trimmer fuel lines
Fuel lines become brittle over time and can crack or tear. Replace a fuel line that's brittle or damaged. Be careful to install new fuel lines on the engine the same way the original fuel lines were configured.
If the line trimmer won't start even though there's fuel in the tank, the carburetor could be the problem. Follow these instructions to replace the carburetor in under 30 minutes.
If the line trimmer engine won't start even though there's fuel in the tank, the carburetor could be the problem. Follow these instructions to do the job in under 30 minutes.
Use the advice and tips in these articles and videos to get the most out of your grass line trimmer.
Tune of your grass line trimmer, following the steps in this video.
Follow the steps in this video to replace a leaking fuel line in a line trimmer.