Ethanol Frequently Asked Questions

What is ethanol?
Ethanol is grain alcohol derived from corn, switchgrass, sugarcane and other sources. When denatured for use as a motor-fuel, it's commonly mixed with regular gasoline in various quantities.

What is E85?
Ethanol/gasoline blends are commonly referred to by the letter "E," meaning ethanol followed by a number denoting the percentage of fuel by volume that is ethanol. E85 is an ethanol/gasoline blend at 85 percent ethanol and 15 percent unleaded gasoline. Other common blends are E10 and E5 (meaning they contain 10 percent ethanol/90 percent gasoline and 5 percent ethanol/95 percent gasoline respectively).

Many vehicles built in the early part of the 20th century were designed to run on ethanol, gasoline or a combination of the two. As gasoline became less expensive and therefore, more popular, ethanol and ethanol-compatible vehicles became rare.

What are the risks?
Ethanol's effects on older cars are many and varied. Depending on the exact make, model and year of your vehicle, as well as the percentage of ethanol in your fuel, you may experience any of the following:

• Galvanic Corrosion
  
  Corrosion caused by contact between two dissimilar metals when the metals are in contact with an electrolyte, like ethanol. It looks like this.
• Deterioration or swelling and hardening of rubber components
  
  Rubber components like fuel hoses, carburetor seals and gaskets, and fuel pump seals may be hardened, dissolved or distorted by contact with ethanol. This may lead to fuel leaks.
• Oxidization Caused by Water
  
  Ethanol holds water very readily and can expose fuel system components and steel gas tanks to rust. This is especially prevalent in boats.
• Fiberglass Fuel Tank Damage
  
  Even low concentrations of ethanol have been shown to damage fiberglass fuel tanks. Ethanol dissolves the lining of fiberglass fuel tanks, often depositing a dark "sludge" inside marine engines causing costly damage. Eventually, fiberglass tanks dissolve until they fail, leaking fuel.
• General Corrosion, Pitting and Rust on Metal parts
  
  Metal parts, such as in-tank fuel pumps and carburetor floats, may be subject to pitting, rust or corrosion when in contact with ethanol blends.

• If you do run your older vehicle on ethanol-blended gas, you might want to run it completely out of gas before storing it for an extended period.
• Check out "Parts Bin" on this site (Coming Soon). If originality isn't a major concern, you might find it worthwhile to replace some of your fuel system components with ethanol-safe parts. You can always revert back in the future.