Will Diesel Fuel Ruin My ATV Engine?

Rick Sosebee
by Rick Sosebee
A fuel mix up is cause for concern

Will diesel fuel ruin my ATV engine? That’s what one of our readers asked the ATV AnswerMan after an accidental fuel mix up.

Here exactly what reader Rachel asked the AnswerMan, followed by his answer:

One of my kids put diesel instead of gas in our ATV will this ruin the engine? She drove it a little ways and it stopped running!

Sorry to hear that you had a fueling mix up. The good part about this is that it was not a diesel engine getting a dose of gasoline. The diesel has more oils in it so if it is removed from the tank and the carburetor is drained quickly then you will have nothing to worry about. There are, however, a few things you will want to do now that the diesel has been ingested.

My first thought is to change the spark plug. This will ensure that the fresh gasoline gets a good spark and things runs as good as possible when the ATV is started once again. My second thought would be to completely drain the tank and if it is a carbureted engine you can drain the carburetor bowl as well. This simply gets the diesel completely out. You might even smell the oil to see if it has an odor of diesel fuel. To be safe I might simply change the oil anyways. I doubt this would harm the engine’s reciprocating parts, but it’s not a bad idea to do so.

Finally, add some real gasoline to the tank and if it is a carbureted engine maybe let a little flow through the carburetor bowl drain just to flush things out. It will take only a second to get the diesel out this way so don’t think you have to let a gallon of fuel run through this drain. This will get any diesel left in the fuel line out of the system completely. Now it is time to go ride that beast. Monitor the engine for the first few rides and be sure to separate the diesel cans from the gas cans in the future!

Rick Sosebee
Rick Sosebee

Whether he is in Mexico covering the Baja 1000, building ATVs for local racers, or out enjoying the trails, Rick’s passion shows in his stories. Learning to wrench his own machines from his grandfather, Rick also has an undying appreciation for the mechanics of off-road vehicles. Do not let the dirt and mud fool you, though, as Rick also has a deep love for street cars.

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