All gasoline currently available is intended for automobile use. Small engine manufacturers (including those who design motorcycles, boats, recreational equipment and lawn and power equipment), therefore, design their engines around the fuels made for automobiles. Since the mid-1980s, manufacturers have indicated that ethanol-blended fuels could be used in equipment with small engines, with certain precautions. It is very important to consult the owner's manual to review the use of ethanol blends for the particular make of your small engine.

Materials
In the past, some manufacturers of small engines expressed concern that the materials may not be compatible with ethanol. The companies have performed their own testing, and most accept the use of ethanol-blended fuels.

Lubrication
Small engine manufacturers have expressed some concerns about inadequate lubricity resulting from the use of ethanol blends. Tests conducted by Valvoline Oil Company have shown a slight increase in lubricity, and have put these concerns to rest.

Storage/Phase Separation
Because ethanol absorbs water in the fuel tank and lines, it can help to prevent the accumulation of water in the gas tank. However, if excessive water is absorbed, a phase separation could occur, resulting in a mixture of alcohol and water in the bottom of the tank. This would make it very difficult for the engine to operate and can cause corrosion. Even at 70% relative humidity, with the cap off of the fuel tank, it would take hundreds of days for the ethanol to absorb this much moisture. By taking caution that no water enters the system, ensuring that the equipment has a properly sealing tank cap, and by filling the tank before extended storage periods, the probability of excessive water in the tank can be minimized. Some manufacturers recommend draining the tank and system before storage. In environments with high humidity, this is the best method of preventing water accumulation. Some manufacturers may also recommend treating the fuel with a stabilizer to inhibit the oxidation and subsequent deterioration of the gasoline during storage.

Over-blends
While some small engine manufacturers may express concern about blends with levels of ethanol that are too high, it is important to remember that the Canadian General Standards Board regulates fuel quality and prescribes the limit of ethanol in fuel as up to 10%. All gasolines sold in Canada (ethanol blends included) must meet these regulations, and those who blend their fuels with ethanol are extremely careful not to over-blend, due to the higher cost of the ethanol component.

Enleanment
Ethanol 'enleans' the fuel by providing it with additional oxygen, and thereby raises the air/fuel ratio, which may benefit engines that have not recently been tuned, or that have dirty air filters. Some manufacturers may require an adjustment in air intake to correct the air/fuel ratio for some small engines. In some applications, such as with boats and snowmobiles, where there is extended operation at wide-open throttle (WOT), the owners manual may suggest a jet-size change to restore the intended air/fuel ratio. Snowmobiles and other equipment used in extreme cold often specify a rich air/fuel ratio, and the engines may be sensitive to enleanment.

Only a few manufacturers may make these recommendations, but it is very important to consult the owners' manual. Even if some manufacturers discourage the use of ethanol-blended fuels for their equipment, it does not mean that they are lower quality fuels. It may simply be that the particular manufacturer has not yet conducted a test program or wants more field experience with these fuels.

"Downstream Alternatives" (1996), lists a review of "power and recreational manufacturers' positions on oxygenated fuel use", based on new or late model equipment.

Manufacturer
Ethanol
  
Manufacturer
Ethanol
Power Equipment
    
Motorcycle
  
Am. Yard Prd/Roper/Rally
yes*
   Harley Davidson
yes
Ariens
yes1
   Honda
yes
Bolens/Troy-Bilt
yes*
   Kawasaki
yes
Briggs and Stratton
yes
   Suzuki
yes*
Coleman
yes*
   Yamaha
yes
Cub Cadet
NM
  
Recreational
  
Dixon
yes
   Arctic Cat (Arctco)
yes*
Echo
yes
   Honda
yes
Grasshopper
NM
   Kawasaki
yes
Homelite
yes
   Polaris
yes*
Honda Power equipment
yes
   Skidoo/Bombardier
yes
John Deere (4 stroke)
yes
   Suzuki
yes*
Kawasaki
yes
   Yamaha
yes
Kohler
yes
  
Boats/Marine
  
Kubota
NM
   Honda
yes
McColloch
yes*
   Kawasaki
yes
MTD
yes
   Mercury
yes*
Onan
yes*
   OMC (Johnson/Evinrude)
yes*
Poulan/Weedeater
NM
   Pleasurecraft
yes*
Ryobi
yes*
   Tigershark (Arctco)
yes*
Sears
yes*
   Tracker
yes*
Shindaiwa
NM
   Yamaha
yes*
Simplicity
yes
      
Snapper
NM
      
Stihl Inc.
NM
      
Tecumseh
yes*
      
Toro/Lawnboy
yes
      

LEGEND

yes = permitted/approved
yes* = approved but may contain precautionary language or require modification
yes1 = approved by engine manufacturer but not equipment manufacturer
NM = not mentioned in owner's manual

  

Owner's Manual
It is very important to consult your owner's manual or engine manufacturer about using ethanol-blended fuels. If the manual is unclear, consult a dealer for the applicable brand of equipment.

Where Can I Get More Information?
Canadian Renewable Fuels Association
90 Woodlawn Rd. W.
Guelph, Ontario N1H 1B2
Telephone: (519)-767-0431
Fax: (519)-837-1674
E-mail: publicinfo@greenfuels.org

References

Rev. 21/10/98
682