Using the wrong type of gas or not caring for it properly is one of the primary reasons you’ll experience a starting or running issue with your pressure washer.
A Generac pressure washer requires unleaded gasoline with a minimum octane rating of 87 and a maximum ethanol content of 10%.
When working with gas, always work in a well-ventilated area and away from combustible items. Allow the engine to cool for a few minutes and slowly remove the gas cap. The tank could be under pressure.
Follow all safety precautions found in the Generac operator’s manual to minimize injury.
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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.
Choose the Right Gas for a Generac Pressure Washer
It can get a little confusing knowing just what type of gas to select for your Generac pressure washer. With so many different types of fuel offered at fuel stations today, it’s important to know what to look for and why.
Low Ethanol Content
Ethanol is an alternative fuel that is added to gasoline so it is a little environmentally friendly. This product is often made from corn or another high-starch plant.
Ethanol naturally attracts moisture. This moisture and ethanol combination can leave behind varnish that coats and gums the fuel system causing fuel restrictions.
It is also highly corrosive and can degrade plastics causing components to prematurely fail on your pressure washer.
Because of its negative effects on the fuel system, always choose gasoline with an ethanol content no greater than 10%. The lower the ethanol level, the better. Never use fuels sold as E15, E30, or E85. These fuels contain up to 15%, 30%, and 85% ethanol.
Use Fresh Gasoline
Gasoline can begin breaking down as soon as 30 days after purchase. Because of this, it’s best to purchase fresh gasoline and consume it within this time.
If you purchase more gas than you can use within 30 days, add a fuel additive to stabilize the gas so it lasts a little longer before it begins to break down.
Add a Fuel Stabilizer
Add a fuel stabilizer to gasoline while it is still fresh. Fuel additives cannot reverse the effects of old gas.
I like to add Sea Foam Motor Treatment to every tank of gas. Sea Foam not only stabilizes gas but also cleans the fuel system and reduces moisture. It helps minimize problems that can develop from running old fuel.
Another good fuel additive alternative is STA-BIL.
Ethanol-Free Fuel (Optional)
Using an ethanol-free gas will avoid the negative effects ethanol has on the pressure washer. While ethanol-free gas is better to run through your Generac, it is the more expensive fuel choice.
Ethanol-free gas can be purchased at some fuel stations. It is sold as recreation fuel or REC-90.
It can also be bought in canisters at your local hardware store.
Tips for Purchasing and Storing Gas for Your Generac Pressure Washer
Using the wrong kind of gas or old gas in a Generac pressure washer can cause starting and running problems. Follow these quick tips when choosing and storing gas:
- Always use fresh gas and consume it within 30 days.
- Use unleaded gasoline with a minimum 87 octane rating and a maximum 10% ethanol content.
- Add a fuel stabilizer when you are unable to consume gas within 30 days.
- Store gasoline in a dry cool location away from combustible products.