Portable generators are most essential when there’s a power outage. In such emergencies, it’s frustrating to see your generator turning off frequently after it is turned on.
This can occur due to a variety of reasons. Overloading is the chief cause of this issue. However, other causes might also prevent a generator from running smoothly.
For instance, a blocked carburetor, bad exhaust, sensor failure, or battery issues can affect the functioning of the generator. When these causes remain unchecked, the generator fails to run smoothly and tends to turn off after a few minutes of its start.
If you are facing a similar issue or you have a generator at home, this guide is for you. We have listed all the possible reasons because of which a generator won’t stay running.
You need to identify the cause of the issue and fix it as directed in a later section of this guide. So, without any further delays, let’s first know the various reasons that affect the smooth functioning of a generator.
Why does my generator keep shutting off?
Are you wondering why your generator won’t stay running for more than a few seconds when started?
Here is a list of reasons that can be the answer to your question.
Your generator runs and then shuts off? Probably it’s because of power overload. If yours is an old generator, overloading is likely to occur because old generators weren’t designed to detect overload and shut down power accordingly. This feature can be found in the latest models though.
Modern-day generators can detect power overload. Whenever such a situation occurs, they shut down, preventing a major accident. Overloading occurs when you connect multiple appliances to the generator and its rated wattage exceeds.
Clogged fuel cap
When the generator operates, fuel from the tank flows into the carburetor and other parts of the generator engine. While the fuel flows out of the tank, there is a space created that is occupied by air. This air clogs up the fuel cap over a period. A generator refuses to stay running when the fuel caps are clogged.
When the fuel cap is clogged, air won’t flow back into the tank where a space has been created by the fuel flowing out of the tank. In such cases, a vacuum is created in the tank, which obstructs the flow of fuel out of the tank into the other parts of the generator. This explains why a generator starts but won’t stay running when the fuel caps are clogged.
The purpose of the carburetor is to convert fuel into electricity. When the generator operates, gasoline-like ethanol attracts moisture. Over time, this moisture tends to corrode the inside of the carburetor. It also corrodes the fuel tank if neglected.
All of this results in carburetor clogging. If your generator makes loud cranky sounds while operating, it means that the carburetor is not in proper condition. If the carburetor isn’t inspected and replaced, the generator will stop working eventually.
Generator Battery Problem
Have you been noticing your generator starts and then dies ? It can be due to a failed battery.
The battery powers some of the important parts of the generator like motors, engine, etc. When the charger is faulty, it overloads the battery. When this is done multiple times, the battery fails to function properly. Sometimes, the battery itself is faulty. In both cases, you must get the battery and the charger inspected and replaced by a professional.
A faulty exhaust pipe of the generator can also be the cause of this issue. Sometimes, it’s defective. When it is so, the generator’s functioning is hindered. It cannot function in the way it is designed to. When the generator is made to run with a bad exhaust, its longevity decreases.
The latest models of generators have sensors fitted into them. As a result, this issue can be found only in the latest models of generators. Like all other parts, a sensor can be faulty. With a faulty sensor, a generator cannot behave properly. A faulty sensor solely can be the reason why your generator keeps shutting off.
Low water levels
A few models of generators fail to run smoothly when there’s insufficient coolant. Water is usually used as a coolant in most generators.
It’s poured into the radiator of the machine. Now, if the amount of water present in the radiator is too low to cool down the machine, it automatically shuts down to prevent other parts from getting damaged.
Generators can detect a rise in temperature because the latest models come with a temperature gauge. Whenever the machine detects a temperature rise, it shuts down automatically.
Fuel system problems
The various parts of the fuel tank are interconnected with one another by valves and narrow pipes. Over time, these pipes can get clogged or corroded, or damaged. When this happens, the functioning of all the parts is affected.
In case there’s no pressure equilibrium in the fuel system, the pipes can get air locked. Sometimes, they bend, cutting off the fuel supply to the various parts. Other times, there might be leakage.
No matter what happens, in each of these cases, the combustion chamber and the carburetor wouldn’t get enough fuel to run properly. This will undoubtedly hinder the proper functioning of the machine.
The latest models of generators usually do not suffer from this issue. Old generators tend to experience engine failure as they aren’t as strong as the latest ones.
Needless to say, when the engine fails and stops running, the generator automatically shuts down. This is a complex problem and only a professional can fix it.
Dirty or malfunctioning spark plug
Sometimes the spark plug accumulates dirt. When this happens, it fails to produce enough spark to ignite the fuel or air mixture. Consequently, the whole process of combustion fails. This ultimately affects the functioning of the engine and the generator tends to shut down when turned on.
How to fix a generator that won’t stay running
Now that we have examined the various causes that prevent generators from running continuously, we would go through the ways to fix the issue. The ways listed above can be done by homeowners, without requiring professional help. If you notice no difference even after following the methods listed below, you must call a professional then.
Let’s go through the ways to fix a generator that shuts down when turned on.
Check to See if Your Generator Is Getting Enough Fuel
If your generator starts and then stops, you must check its fuel tank first. Your generator might be running on low fuel, because of which it shut down midway. But, if you find out that the gas tank has sufficient fuel but the generator won’t stay running, you must inspect the fuel filter or the fuel pump in that case.
Change the Fuel Filter
Despite having sufficient fuel, the generator might stop working because of a clogged or damaged fuel filter. In that case, changing the fuel filter is all you need to do. Follow the below-mentioned steps in that case:
- Take out the old filter from the engine.
- Pour the lubricating oil that has been recommended or instructed in the manual into the oil filter.
- Now, leave the oiled fuel filter for some time. Again pour some oil into it.
- Keep pouring oil multiple times unless the air in the filter is discharged and the fuel filter is completely filled with oil.
- Now, before it’s time to install the filter into the filter sear, apply a little amount of diesel oil onto it. After fitting the filter into the sear, rotate it until it’s fitted tightly.
Open the Fuel Valve
Sometimes the fuel valve also gets clogged or jammed. If your generator runs then shuts off, it can be due to a jammed fuel valve. If the fuel valve is closed, the generator wouldn’t start at all. But, if it starts and then shuts down, it means a partially clogged valve is preventing enough fuel from reaching the engine.
Clean a clogged carburetor
We have already discussed how a clogged carburetor can be the cause of a malfunctioning generator. If your generator starts but won’t stay running, inspect the carburetor without fail. It might get sticky or clogged or gummy. This hinders the proper functioning of the generator’s engine
To clean the carburetor, drain the float bowl. Use a chemical carburetor cleaning solution to clean the carburetor. Remove the dirt, grease, and sludge present inside. This will unclog the carburetor and enable it to do its work properly.
If your generator starts then stops even after cleaning the carburetor, it’s time to replace it with a new one.
Clean the Air Filter
When your generator keeps shutting off, you mustn’t forget to check the air filter. To clean the air filter, follow the steps mentioned below:
- Use a liquid detergent to clean the foam filter. Clean it properly. Let it dry. If there’s excess water remaining inside, squeeze it out.
- Once the air filter is dry, apply engine oil to one side of the filter. Now soak up the excess oil by putting a cloth on top of it. Make sure there’s no excess oil dripping from the filter.
- Now, fit the air filter into its right place. Make sure the side soaked in oil faces the engine.
- Now it’s time to replace the air cleaner cover.
Prevent Vapor Lock
Sometimes the fuel inside the engine gets overheated. It vaporizes as a result. In the process, it blocks the fuel delivery passage. This affects the functioning of the generator. It shuts down repeatedly after being started.
To solve this issue, you must put fresh oil into the fuel tank. Use a fuel stabilizer as much as you can. While doing so remember to put only fresh oil and pour the oil that’s recommended in the manual.
Check the exhaust system
If you notice your generator starts but won’t stay running, check the exhaust system. Ensure it’s running properly. See the amount of smoke it’s producing. Is it normal or excessive?
Usually, a simple blockage in the exhaust system causes the generator to malfunction. If you notice that the smoke production is too much, call a professional without delay because generator smoke is extremely harmful to one’s health.
As we already mentioned, sometimes a generator runs then shuts off due to insufficient engine oil. Therefore you must check the engine and see if there’s enough oil inside. The latest models of generators are designed to shut down automatically when there’s insufficient oil inside
Replace a faulty spark plug
Sometimes a faulty spark plug prevents your generator from starting altogether. Other times, the generator starts but won’t stay running for more than a few minutes. If a faulty spark plug is the cause of the problem, clean or replace it.
Firstly, remove the spark plug from the generator. See if there’s any dirt or debris present inside. Use petrol and a knife to bring out the debris accumulated inside. Before refitting it in position, make sure it’s dry.
If you notice a blue spark, it indicates that the spark plug is in proper condition. If there’s no spark produced or very little produced, it means the spark plug cannot ignite the fuel. If cleaning the coil didn’t work you must buy a new one and fit it properly. While buying a new one, remember to buy a plug of a similar type.
The Bottom Line
As you can see, a generator starts and then stops due to a variety of reasons. Mostly, this problem occurs due to the overloading of power. Unplug some of the appliances and see if the generator functions properly. If it does, it means overloading was the cause of the problem.
However, other reasons can also give rise to the issue. Therefore, try to find out the cause of the problem first and then proceed to fix it. For safety reasons, we would advise homeowners to call a professional and let him inspect the machine.