How to troubleshoot your Generac generator when the engine won't start
When you can’t start your Generac generator engine, make sure the tank has fuel and that the fuel is fresh; stale fuel can become watery and won’t ignite well. Tune up the engine to give it the best chance of starting. Check the spark plug and replace it if it’s covered with oil or other deposits.
If your generator uses a battery, charge or replace the battery if it won’t power the starter to spin the engine. If you have to pull the starter rope to start the engine, replace the recoil starter if it doesn’t spin the engine when you pull the rope. Replace the starter rope if it’s broken.
Some Generac engines have a low oil level switch that prevents the engine from starting and running if the engine's oil is low. Check engine oil level and add oil if needed.
Test the ignition system using a spark plug tester. Replace the safety switch or the ignition coil if the spark plug isn’t getting current through the ignition system.
Carburetor problems often prevent your Generac generator engine from starting. Replace or rebuild the carburetor if it’s clogged.
Check your owner's manual for additional troubleshooting tips to help you get the engine started.
Frequently replaced parts in Generac generators
- Carburetor. The engine carburetor is a component that mixes the air and fuel to create a combustible mixture that enters the engine cylinder and gets ignited by the spark plug to drive the piston.
- Air filter. The air filter prevents abrasive particles from entering the engine's cylinders, which could cause mechanical wear and oil contamination.
- Battery. On electric start engines, the battery provides the 12 volts needed to power the starter.
- Spark plug. The spark plug is the engine device responsible for delivering electric current from the ignition system to the combustion chamber of the cylinder. This current ignites the compressed fuel/air mixture by means of an electric spark, while containing combustion pressure within the engine.