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HomeRepair HelpGenerac RepairGenerac Pressure washer runs rough Repair
Generac Pressure washer runs rough
If your Generac gas pressure washer is running rough, surging, sputtering, hesitating, or the engine runs poorly, start with the carburetor. Stale or ethanol-blended fuel left in the carburetor is one of the most common causes on seasonal equipment. Old fuel can leave a sticky residue that clogs the carburetor, main passages, or jets, preventing the engine from getting the correct fuel mixture. Clean the carburetor with carburetor cleaner, then install a carburetor repair kit or replace the carburetor if cleaning does not help. Next, check the fuel filter, which can also become restricted by old fuel. A clogged fuel cap vent can limit airflow into the fuel tank and cause the engine to run poorly or stall, so briefly loosening the cap can help confirm the problem. A clogged air filter or pre-cleaner can also restrict airflow, although a dirty pre-cleaner is less common. Always shut off the pressure washer and disconnect the spark plug wire before servicing. Enter your model number to find the exact replacement carburetor, fuel filter, fuel cap, air filter, or pre-cleaner for your Generac pressure washer.
01 - Generac Carburetor
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the pressure washer for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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02 - Generac Carburetor Repair Kit
The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the pressure washer for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the carburetor and cause the engine to run roughly. If the carburetor is clogged, try cleaning it with carburetor cleaner. If cleaning the carburetor isn’t effective, rebuild or replace the entire carburetor.
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03 - Generac Fuel Filter
The fuel filter might be clogged. A clogged fuel filter is most commonly caused by leaving fuel in the pressure washer for a long period of time. Over time, some of the ingredients in the fuel may evaporate, leaving behind a thicker, stickier substance. This sticky fuel can clog up the fuel filter and cause the engine to run roughly. If old fuel was left in the pressure washer, drain the old fuel from the fuel tank and replace the fuel filter.
Highly Likely
04 - Generac Fuel Cap
As fuel is consumed, the pressure in the gas tank rises. To relieve this pressure, the gas cap uses a small vent to allow air to enter the gas tank. If the gas cap vent is clogged, air won’t be able to enter the gas tank, and the pressure in the tank will begin to rise. When the pressure in the gas tank exceeds the pressure in the engine, the engine will stall or run poorly. To determine if the gas cap vent is clogged, try slightly loosening the gas cap and then starting the engine. If the loosening the gas cap allows the engine to stay running, this indicates that the gas cap vent is clogged. If the gas cap vent is clogge...
Highly Likely
05 - Generac Air Filter
The air filter may be clogged. If the air filter is clogged, the engine will get too much fuel and not enough air. As a result, the engine may run roughly. If the air filter is clogged, replace it.
Highly Likely
06 - Generac Spark Arrestor
The spark arrestor is a small screen that prevents the engine from emitting sparks. Over time, the spark arrestor can become clogged with soot. If the spark arrestor is clogged, the engine may run roughly. To unclog the spark arrestor, remove it and clean it with a wire brush. You may also replace the spark arrestor.
Highly Likely
07 - Generac Pre-Cleaner
The pre-cleaner might be clogged. However, this is rare.
Highly Likely
Frequently Asked Questions
Why is my Generac pressure washer running rough, surging, or sputtering?
Can a clogged carburetor cause my pressure washer engine to run poorly?
How do I check the fuel filter, fuel cap, and air filter when my pressure washer runs rough?
How do I find the correct Generac pressure washer carburetor or filter part?
When should I call a technician for a Generac pressure washer that runs rough?