Is it safe to run E15 high-ethanol fuel in an older engine?
High-ethanol fuel blends like E15 contain more alcohol than legacy fuel systems and older carburetors can handle. This higher alcohol content attacks and destroys older rubber components throughout the fuel system, including the fuel lines, pump, and carburetor.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Diluting the high-ethanol fuel with regular 87 or 89 octane or ethanol-free gasDid this help you?
- 2Re-jetting or tuning the carburetor for a richer mixture to compensate for lean running conditionsDid this help you?
- 3Upgrading all fuel system hoses, seals, and gaskets to PTFE or SAE30R10 rated componentsDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“The 88 is cheaper because it has more ethanol in it. Your truck is already not meant for the 10% in the regular gas they sell. You don't want to run gas with even more ethanol.”source ↗
“88 is high alcohol. Alcohol will destroy the old rubber in your fuel system. The older the rubber the faster it will happen. Everything. Carb, fuel pump, fuel lines etc.”source ↗
“Would it hurt to run a tank of 88 every once in awhile. My truck has a new carb and fuel lines and tank. It’s an old 350.”source ↗
Where this came up
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