how to start a generator that has been sitting

3 min read 05-02-2025

how to start a generator that has been sitting

Starting a generator that's been sitting unused can feel daunting. But with a little preparation and the right steps, you can get it running smoothly. This guide walks you through the process, ensuring your generator is ready for when you need it most. This applies whether you're using a portable gas generator, a standby generator, or even a larger diesel model. The key is preparation and following safety guidelines.

Pre-Start Inspection: Safety First!

Before even attempting to start your generator, a thorough inspection is crucial. This preventative maintenance will save you headaches and potential hazards down the line.

1. Fuel System Check

Inspect the fuel: Old gasoline goes bad, causing varnish and gum to form. This can clog fuel lines and damage the carburetor. If your generator has been sitting for more than 3 months, drain the old fuel completely. Use a siphon pump or carefully drain it from the tank. Never pour old fuel down a drain; dispose of it properly according to local regulations.
Check fuel lines: Look for cracks, leaks, or deterioration in the fuel lines. Replace any damaged lines immediately.
Check the fuel filter: A clogged fuel filter can prevent fuel from reaching the engine. Replace it if necessary. This is a cheap and effective preventative measure.

2. Engine Oil Check

Check the oil level: Low oil can severely damage the engine. Check the dipstick and add fresh oil if needed, using the type and amount specified in your owner's manual.
Check the oil condition: If the oil is dark, dirty, or smells burnt, change it completely. Old oil loses its lubricating properties and can damage your engine.

3. Inspect the Air Filter

A dirty air filter restricts airflow, reducing engine performance and potentially causing damage. Replace the air filter if it's dirty or damaged.

4. Inspect the Spark Plug (Gasoline Generators)

Remove and inspect: Carefully remove the spark plug and inspect it for damage or fouling. A fouled plug will hinder starting.
Clean or replace: Clean the spark plug with a wire brush if it's dirty. Replace it if it's damaged or severely fouled. A gap check might also be needed (consult your owner's manual).
Proper gap: Ensure the spark plug gap is correctly set according to the specifications in your owner's manual.

5. Battery Check (If Applicable)

If your generator has a battery, check its charge. A weak or dead battery will prevent starting. Charge the battery if needed or replace it if necessary.

Starting Your Generator

Once the pre-start inspection is complete, you're ready to try starting the generator.

1. Ensure Proper Ventilation

Operate the generator outdoors in a well-ventilated area, away from any flammable materials. Carbon monoxide poisoning is a serious risk. Never operate it indoors.

2. Add Fresh Fuel

Add fresh, clean gasoline (or diesel, depending on your generator) to the fuel tank. Don't overfill the tank.

3. Follow the Manufacturer's Instructions

Consult your generator's owner's manual for specific starting instructions. The process may vary slightly depending on the make and model. Generally, this involves turning the fuel valve to the "on" position, priming the carburetor (if necessary), and then attempting to start the engine.

4. Troubleshooting

If the generator won't start, here are some common issues:

No fuel: Double check that you added fuel and that the fuel line isn't clogged.
Dead battery: Check the battery voltage. A weak battery might require a jump start or replacement.
Clogged air filter: A dirty air filter can restrict airflow and prevent starting. Replace the air filter.
Spark plug issues: Check the spark plug to ensure it's not fouled or damaged.
Fuel issues: The fuel could be old, contaminated, or the carburetor might be clogged.

If you've checked these points and your generator still won't start, it's best to contact a qualified generator repair technician.

Post-Start Checks

After successfully starting your generator, let it run for a few minutes. Check for any unusual noises, smoke, or leaks. If everything looks and sounds normal, you're good to go!

Remember to consult your owner's manual for detailed instructions specific to your generator model. Regular maintenance is key to ensuring your generator runs smoothly and reliably when you need it.

Maintaining Your Generator for Future Starts

Regular maintenance is key to extending the life of your generator. These steps will help ensure it's ready when needed:

Regular oil changes: Change the oil according to the schedule in your owner's manual.
Fuel stabilizer: Use a fuel stabilizer to prevent fuel degradation during prolonged storage.
Clean air filter: Clean or replace the air filter regularly.
Battery maintenance (if applicable): Keep the battery charged and clean. Consider a trickle charger for long-term storage.
Storage: Store the generator in a dry, clean place. Cover it to protect it from dust and moisture.

By following these steps, you'll ensure your generator starts reliably when you need it most. Remember, safety is paramount, so always follow the manufacturer's instructions and exercise caution when working with gasoline and machinery.