Generator Won’t Start? Here’s Why & What to Do

Your home’s generator keeps the power running no matter how long an outage lasts. It keeps your heating and cooling on and prevents your food from spoiling. But when your reliable backup power cuts out you are left in the dark.

If your generator suddenly stops turning on when you need it, here are some tips on how to fix it from the professionals at LimRic.

10 Reasons Why & Simple Checks to Diagnose Generator Issues

1. Check the Fuel Tank

Firstly you want to check your fuel tank. If your generator has low or no fuel at all, add more. When refueling, make sure you are not using old gasoline as older fuel can lead to engine damage or potential clogging. If the gas is older than 2 months, it’s no good.

2. Check the Oil Level

Having the appropriate amount of clean oil within your generator allows for it to run as smoothly as possible. Using a dipstick, check your oil level while the generator is on a level surface. If the level is too low, add more of the manufacturer-recommended oil.

3. Check the Start Switch

While it may seem obvious at first, always check to see if your start switch is set to “on”. Sometimes mistakes can happen. If it does not start while set to “on”, test the switch’s electrical path using a multimeter tool. If the switch is coming up negative when set to “on”, you may need to replace the start switch entirely.

4. Check the Choke Valve Switch

When starting up your generator, make sure to set the choke valve to the “off” position. Once the unit has warmed up, you can then turn the choke valve on. If the switch happens to be on when you start the generator, you can switch it back to the “off” position and try turning the generator on again.

5. Check the Air Filter

A clear air filter is essential to the combustion process, as it allows for the carburetor to provide needed air to run the generator. So if your generator is cranking but not turning on, a clogged filter may be the culprit. If your air filter looks dirty, change it out with a brand-new one.

6. Check the Spark Plug

This component will wear down with continual use, so make it a habit to check the condition. If there seems to be an electrical issue, use an ignition spark tester to assess the electrical current. If there is a light carbon buildup on the plug, you can clean it off by using a wire brush and carbon cleaner.

You’ll want to replace the plug completely if the carbon buildup is too heavy or there is prevalent wear and cracking.

7. Check the Carburetor

As fuel ages inside your generator, it can cause buildup within the carburetor, preventing combustion and engine startup. If you find there is a clog, use a carburetor cleaner to remove the blockage effectively.

8. Check the Fuel Valve

This valve controls the gas flow from your fuel tank to the carburetor, so any form of clog can stop the start-up process. 

First, check that both the fuel and vacuum relief valves are open to allow the fuel to flow from the tank to the carburetor. If both valves are open but your generator still won’t start, check your fuel line by unplugging the hose from the intake side of the fuel valve. Pour fuel into the hose to check for blockages, while having a bucket ready to catch any fuel that comes through. 

Finally, if your generator has a filter installed between the fuel line and carburetor, check for any potential blockages as well.

9. Check the Oil Level Sensor

This sensor indicates when the engine’s oil level is too low. If the sensor malfunctions, it may register incorrect oil levels. A common cause of this issue is placing the generator on an uneven surface, which can lead to an inaccurate oil level reading.

To prevent sensor malfunctions, ensure your generator is positioned on a stable, even surface before checking the oil level. If the reading still indicates low oil, disconnect the sensor and try to start the engine. If the engine starts normally, the sensor is likely the problem.

To resolve this, simply plug the sensor back in and perform a reboot. If the sensor continues to malfunction after this, it will need to be replaced.

10. Check the Ignition Coil

This component is responsible for sending the needed voltage to your sparkplug, which gets your engine up and running. For this check, you can use the ignition spark tester from before to check for coil failure. If the coil is unable to provide voltage, you’ll need to replace it.

Why Is My Generator Running but Has No Power?

When your generator is up and running perfectly but you still have no power, the blame can usually be placed on one thing: residual magnetism. Simply put, this is the leftover magnetism from the previous magnetic field that your generator created when it ran last.

These magnetic leftovers provide enough initial electricity to get your generator up and running and assist with your generator’s production of power as it continues to run. If there is no residual magnetism for the generator to use, your generator can’t produce any power when it starts up.

Residual magnetism can be lost due to:

• Lack of generator use 
• Running for too long with no load
• Turning off the unit before load disconnection 
• Vibrations from long-distance travel (Usually seen in brand-new generators)

So what do you do? Use a 12-volt battery and connect it to your generator’s field terminals, which is where the electrical current is supplied to the field coils. This method is called “flashing the field” or simply “flash”. By doing so, your generator has the residual magnetism needed to start producing voltage.

We’re an Authorized Generac Dealer

If you’re having ongoing problems with your generator, consider switching to a reliable brand like Generac. As an authorized Generac dealer, LimRic’s team of experts can help you with a quote for a brand-new unit. 

Already have a Generac? No problem, our knowledgeable electricians know the ins and outs of the brand and can assist with troubleshooting any issues.

When to Call for Emergency Generator Repair Services

When you have done all you can, or you are not sure if you can diagnose the problem by yourself, it’s time to bring in the pros. When generator problems are plaguing you, LimRic’s expert emergency generator services are just the remedy you need. Our team of licensed electricians knows all about generators.

With years of experience and the proper tools, we fully inspect your unit to find the issue and provide repairs. Blackouts can happen out of the blue, so when your lights go out and your generator fails, LimRic provides the emergency electrical service you need. 

Call LimRic today at (843) 380-2175 or schedule an appointment online. Our expert electricians provide our comprehensive generator services across the North Charleston area including Summerville, Mount Pleasant, Goose Creek, Ravanel, and more of the surrounding areas of the South Carolina Lowcountry.