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When you need to use your portable generator, you expect it to work well. Even the best portable generators sometimes have issues. It's really important to treat them well so they'll start first time.
Pulling your generator out of the garage then realizing it won't start can be frustrating.
If you have this problem, do not stress because there is a good chance the problem is minor and you can fix it. Diagnosing the problem with your portable generator will be the first step to take. You will have an easier time solving a problem when you know the cause.
There are some common causes of a generator failing to start. Below are some of the common causes and what you can do when in such a situation.
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Use Fresh Fuel
The most important thing when running a portable generator is fuel. You need to have enough gas in the tank for it to start. If you have not used your generator in a long time, consider replacing the old fuel with fresh fuel. Fuels degrade when left unused for long. One way to know your fuel has degraded is by having a closer look. If the fuel looks cloudy or there has been separation. This could be the main reason why your portable generator is not starting.
Fuel older than two months can be damaging to the engine of the generator. Siphon the gas from the fuel tank then fill it up using fresh fuel. Make sure you have emptied both the tank and the carburetor before refilling it. The best thing is preventing this from happening. You can do it by running your portable generator dry after using it. You should also consider adding a fuel stabilizer.
Fuel is the most important thing for a portable generator; make sure you have fresh fuel.
Check the Spark Plug
To do this, you will need to pull the spark plug. If it is dirty, take some carb cleaner and use it in cleaning it up. You can also use it to clean the cylinder, provided you have removed the spark plug. Some signs of damage include cracked porcelain insulator, damaged or burned away electrode, or a heavy carbon buildup at the electrode. If your portable generator is still not starting after doing this and the other steps, then you might need to replace the spark plugs. because the spark plugs look fine doesn’t mean that they work. They can go bad and wear out while still looking fine.
There is a spark plug tester you can use when determining whether a plug is defective. When cranking the engine, you should see a strong spark between the terminals. Try clearing away deposits using a brush then try starting the generator.
Replace the plugs if they are defective then try starting the generator. Replacing plugs shouldn’t be too much stress because they are cheap. You need to get a spare spark plug so you can use it anytime you have this problem.
Check the Air Filter
Airflow is a must for a portable generator, and a clogged air filter can make this harder. If it is clogged with dust and debris, the carburetor is not going to get the air it needs for combustion. Accessing and inspecting the air filter is easy. Pull the air filter of the generator and see if it is clogged. If the air filter doesn’t look that bad, you can clean it. Give it a light whack on the counter-top or the floor or shaking off the dust.
If you pull out the air filter and it looks worn or clogged up, then you have to replace it. They are cheap, and this is why you should try having a spare air filter. When buying an air filter for your generator, make sure you read the owner’s manual to know the specifications of the air filter. There is nothing worse than getting an air filter then realizing it doesn’t fit in the generator. Some people run the generator without an air filter, but you should never do this because you will end up with more damage, and you might be forced to spend a lot of money to fix it.
Check the Fuel Line and Fuel Filter
If your portable generator is still not starting, check out the fuel line and see whether there are any clogs, pinches, leaks, or cracks. There are some instances where the damage can be repaired, but in most cases, you will need to have the line replaced. This problem is not that common, but you can still have a spare fuel line if you are one of those people who like being prepared for anything.
You need to check out the fuel filters because it can get clogged up. Its work is preventing debris from traveling from the fuel line to the generator. Look for where the fuel line attaches to the carburetor then remove it. Check whether there is fuel passing through the filter. If there is no gas draining through the filter, then you need to replace it because it is clogged.
Clean the Carburetor
When old degraded gas reaches the carburetor, it can result in problems. They form clogs in the carburetor and this makes it harder for the new fuel to get through. There are times when using a car cleaner on the orifices and jets will work, and you don’t have to remove it. There are cases when you have to remove it. Remember carburetors can be very sensitive. You should be careful not to scratch it when removing it.
Have a good place to put the screws so you can keep track. Losing some of the smaller parts will make the work even harder for you. If it is your first and not sure about it, then consider watching videos of carburetors before doing it. There are videos you can watch that will guide you through the process. If cleaning it doesn’t work, you might have to replace the entire carburetor. Adding a dash of fuel stabilizer can help.
Generator Still Won't Start? What Else Can I Do?
- Check the oil level and top up if necessary
- Is the generator out of gas?
- Is the choke level in the wrong position?
- Is the low-oil sensor working?
- Are electronics plugged in during start up? If so, make sure they are disconnected
- Is the battery dead?
- If all else fails, check the troubleshooting section of your owner's manual! The answer may well be in there…
When all else fails, read the instructions [Agnes Allen}

Portable Generator Maintenance
Preventing a problem will be way cheaper than fixing it. Save yourself a lot of expenses and stress by performing regular preventative maintenance. Read the portable generator manual and follow the maintenance schedule it lays out.
You need to change the oil after a couple of uses and check the spark plugs and air filter when recommended. Regular maintenance will help ensure your generator works well, especially when you have an emergency. It is normal for a portable generator to sit around unused for long when it is for emergencies.
If you use it only for emergencies, then make sure it runs dry. You can use a fuel stabilizer if you don’t want to do this.
From time to time, start your portable generator.
When faced with an emergency, you don’t want to start stressing and worrying about your generator not starting or running the way it should.
The worst thing you can do is let your portable generator sit and collect dust.
Conclusion
If your portable generator won't start right away, don’t panic because it could be a small problem that you can fix in a few minutes. With basic troubleshooting, you can get the generator to start.
If you do all the above but it still doesn’t start, then your best course of action is letting a certified technician handle it. You should look for a technician handling your generator brand.
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