Cause 1

Fuel Cap

As fuel is consumed by the engine, the level in the fuel tank lowers. To make up for this, the fuel cap uses a small vent to allow air to enter the tank. If the fuel cap vent is clogged, air won’t be able to enter the tank and a vacuum or “vapor lock” will occur. This stops the flow of fuel to the carburetor causing the engine to stall. To determine if the fuel cap vent is clogged, try slightly loosening the cap and then starting the engine. If loosening the fuel cap allows the engine to stay running it is likely clogged and will need to be replaced.

Cause 2

Carburetor Repair Kit

The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the generator for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and prevent the engine from starting. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.

Cause 3

Carburetor

The carburetor might be clogged or have bad fuel in the float bowl. If old fuel was left in the small engine for a long time, some of the volatile ingredients may have evaporated, leaving a thicker, stickier product that is more like varnish or shellac. This sticky fuel can clog up the small jets and ports in the carburetor and prevent the engine from running. The only solution is to drain the old fuel from the float bowl and thoroughly clean the carburetor with carburetor cleaner. If that isn't effective, replace the entire carburetor.

Cause 1

Carburetor Bowl Gasket

The carburetor bowl gasket on the bottom of the carburetor might be dried out or missing. If the leak is coming from the bottom of the carburetor, try replacing the carburetor bowl gasket.

Cause 2

Float Bowl Gasket

The carburetor float bowl gasket on the bottom of the carburetor might be dried out or missing. If the leak is coming from the bottom of the carburetor, try replacing the carburetor float bowl gasket.

Cause 3

Carburetor Gasket

The carburetor gasket might be dried out or missing. If the leak is coming from the bottom of the carburetor, try replacing the carburetor gasket.

Cause 1

Spark Plug

Inspect the spark plug for signs of wear or damage. If the porcelain insulator is cracked, an electrode is burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. To determine if the spark plug is defective, use a spark plug tester. You should see a strong spark between the tester’s terminals when the engine is cranking. If there is no spark, this indicates that the spark plug is defective and should be replaced.

Cause 2

Carburetor Repair Kit

The carburetor might be clogged. A clogged carburetor is most often due to leaving fuel in the generator for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to stall or run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.

Cause 3

Carburetor

The carburetor might be clogged. A clogged carburetor is most often due to leaving fuel in the generator for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to stall or run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.

Cause 1

Alternator

TTo determine if the alternator is at fault, use a multimeter to test it for continuity.

Cause 2

Voltage Regulator

While the engine is running, the voltage regulator sends the proper amount of voltage from the alternator to the battery to keep the battery charged. If the voltage regulator is defective, the battery won't receive enough voltage, causing the battery to drain quickly.

Cause 1

Ignition Coil

The ignition coil sends voltage to the spark plug while the engine is running. If the ignition coil is defective, the engine may not start. Before replacing the ignition coil, ensure that the spark plug is working properly. If you have confirmed that the spark plug is working properly, test the ignition coil with an ignition coil tester. If the ignition coil is defective, replace it.

Cause 2

Carburetor

The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the generator for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and prevent the engine from starting. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.

Cause 3

Spark Plug

Inspect the spark plug for signs of wear or damage. If the porcelain insulator is cracked, an electrode is burned away or damaged, or there is heavy carbon buildup at the electrode, replace the spark plug. To determine if the spark plug is defective, use a spark plug tester. You should see a strong spark between the tester’s terminals when the engine is cranking. If there is no spark, this indicates that the spark plug is defective and should be replaced.