When it seems like you’re not getting good power from your engine and it begins to run sluggish and bog down, it’s important to find the cause and repair it to prevent potential serious damage.
Predator generators bog down and run rough under load due to more load than the generator can handle, a dirty carburetor, a clogged fuel filter, a plugged air filter, a wrong choke setting, or plugged spark arrestor.
Take safety precautions before working on your generator. This includes allowing the engine to cool and disconnecting the spark plug wire.
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Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.
6 Reasons a Predator Generator Bogs Down Under Load
1. Too Much Load is Applied for the Generator Size
Predator offers a variety of generators that are able to handle different load limits. They vary in the wattage the generator can handle.
Exceeding the limit your generator is able to handle will cause the generator to bog down and possibly quit running. Additionally, this may potentially damage the generator and items connected to it.
Before checking the generator for items that can cause it to run rough, check the load limit of your generator along with the wattage requirements of the items you are running with the generator.
You will find the starting watts and running watts for your model listed on the generator. The wattage requirements of the items you are running at the same time must be less than the generator’s running load limit.
The starting load limit is the load the generator can handle temporarily when powering items that will require additional wattage to start an item.
Follow these tips to determine the wattage capacity:
- You will find the wattage of most electrical items listed on a tag attached to the item.
- Some motors require additional wattage to start an item. In this case, the starting wattage should be used when calculating wattage requirements.
- Add the wattage of all items that will be plugged into the generator at one time to get a total.
- This total wattage must be less than the generator’s wattage capacity.
Do not run more electrical items using the generator than it can handle. When the unit bogs down, shut down the generator. Remove all items plugged into the ports. Restart the generator and add one item at a time.
2. Dirty Carburetor
Over time, varnish can build up in the carburetor causing it to not function correctly. Varnish is a result of old gas that will coat the internal parts of the carburetor causing fuel passages to become plugged.
Without sufficient fuel, the fuel and air mixture will not ignite to form the explosion needed to start the engine. A dirty carburetor will need to be removed to be cleaned or rebuilt to get working again.
To clean the carburetor, it’s a good idea to take photos through the disassembling process to make sure the small parts are placed in the correct positions when reinstalling the carburetor.
Remove the carburetor from the generator. Remove as much buildup as you can using a carburetor cleaner. If you find any damaged parts, use a carburetor rebuild kit to replace them. Once cleaned and repaired, install the carburetor.
If working with small parts is not something you want to tackle, you can purchase and replace a complete carburetor instead of tearing it apart to clean and rebuild it. You may need a new Predator carburetor if it still doesn’t function after cleaning it.
3. Clogged Fuel Filter and Sediment Bowl
A fuel filter is used on a Predator generator to keep dirt from finding its way through the fuel system to the engine causing wear and damage.
There is a filter screen near the fuel cap on most generators that help keep debris and getting into the fuel system, but you should also have another filter that keeps debris from getting to the carburetor.
Depending on the model you have you may have one of these types of filters:
- Inline fuel filter (filter inserted between the fuel lines).
- A filter is installed at the bottom of the fuel tank.
- A narrow filter is inserted in the fuel line or fuel component.
It’s best to replace the fuel filter annually if you have an inline fuel filter. You may also find a sediment bowl on some fuel shut-off valves that must be emptied and cleaned regularly.
If you are unsure if a fuel filter is used and where your fuel filter is located, contact a Predator service center for assistance.
4. Plugged Air Filter
The air filter keeps dirt from entering the air intake to protect the engine from the damage that can occur from just a small amount of dirt or debris.
Just like the fuel filter, you should replace the air filter at least once a year and more often if you use the generator frequently or are operating it in dusty conditions.
Tips for maintaining a good air filter:
- Check and clean the filter’s condition regularly to remove dirt and debris.
- Replace the filter annually or if it is damaged or very dirty.
- Use a filter designed for your model generator.
- Never run your generator without a filter.
If you are not cleaning and replacing the filter regularly, the filter can become plugged with so much dirt that the engine won’t get sufficient air. It can cause the engine to bog down, overheat and cause extensive permanent damage.
Check the air filter before each use and clean or replace it if needed. Follow the cleaning instructions found in the Predator operator’s manual.
I have included cleaning instructions for a couple of types of air filters below. Consult your manual if you are unsure of how to clean your type of air filter.
Clean a Predator generator foam-style air filter
- Remove the air filter from the housing.
- Wipe out any dirt remaining in the air filter housing and cover. Don’t allow dirt to fall into the air intake.
- Inspect the foam filter for damage and replace it if needed.
- If the filter is in good condition, clean it in soapy water and rinse it until the water runs clear.
- Squeeze the filter and allow it to dry.
- Coat the filter in a clean lightweight engine oil like SAE 30. Squeeze the filter to remove excess oil.
- Install the air filter.
- Reattach the air filter cover.
Clean a Predator generator paper air filter:
- Remove the air filter from the housing.
- Wipe out any dirt remaining in the air filter housing and cover. Don’t allow dirt to fall into the air intake.
- Inspect the paper air filter. Tap the filter to loosen dirt so it falls from the filter. Be careful not to damage the paper. If the filter is very dirty, damaged, or no longer seals the air intake sufficiently, replace it with a new one.
- Predator recommends trying to blow dust out of the filter with pressurized air.
- Install a clean or new air filter.
- Reattach the air filter cover.
5. Wrong Choke Setting
Another lack of airflow problem that can cause the generator to bog down is when the choke isn’t adjusted after the engine warms to allow sufficient air to get to the engine.
This can be due to forgetting to adjust the choke to the off position once the engine warms. It may also be caused by a bad switch or dial (depending on your model) used to start the generator or a stuck choke.
6. Clogged Spark Arrestor
The spark arrestor screen is a part installed on a Predator generator to prevent sparks and hot material from emitting from the muffler. This is to reduce burn injuries and potential fires.
When this metal screen becomes plugged with a buildup of carbon, the generator will begin to run rough and possibly shut down because hot exhaust air is unable to leave the engine.
Before removing and cleaning the spark arrestor, wait for the muffler to cool to reduce injury. Remove the spark arrestor screen and inspect its condition. Replace the screen with a new one if you find any tears or holes in the mesh screen.
If the screen appears to be in good condition, clean it with a commercial solvent or brush it lightly using a small metal brush to remove soot deposits. Once the screen is clean, place it back onto the muffler.