What kind of fuel should I use in my Honda Marine engine?
Honda engines are designed and certified to run on regular unleaded gasoline.
Gasoline is allowed, by regulation, to contain a variety of additives. The same regulation limits how much of some additives, such as alcohol, can be included in the fuel and still be sold as gasoline. If you look in a Honda product owner’s manual, you will see that a maximum of 10% ethanol is allowed in gasoline (other oxygenates are also listed). Honda engines are designed for good performance and efficient operation using gasoline containing from 0 to 10% ethanol.
E85, a mixture of 85% ethanol and 15% gasoline, has been in the news recently. E85 is an alternative fuel; it is not gasoline. Honda Marine engines are not currently designed or certified to run on E85 or any other alternative fuel.
Always refer to your Honda owner’s manual for a list of recommended fuel and the current approved additives.
How long can I leave gas in the tank?
The length of time that gasoline can be left in your fuel tank and carburetor without causing functional problems will vary depending on a variety of factors.
- Fuel formulations vary by region. Depending on the region where you operate your outboard, fuel may deteriorate and oxidize more rapidly (in as little as 15 days). Please check with your servicing dealer for storage recommendations and precautions specific to your region.
Other factors include:
- The air volume in a partially filled fuel tank promotes fuel deterioration.
- Very warm storage, high humidity and variable temperatures accelerate fuel deterioration.
- Fuel deterioration problems may occur in less than 30 days if the gasoline was not fresh when you filled the fuel tank. Purchasing fuel from a busy, reputable gas station is recommended.
Instructions regarding the maintenance and storage of your specific outboard model are contained in the STORAGE section of your Honda owner's manual. This section covers all aspects of storage such as adding fuel stabilizer and draining the fuel tank and carburetor, as well as storage precautions and removal from storage.
What kind of problems can occur from old gas?
In storage, gasoline immediately starts to oxidize and deteriorate. The older it gets the more it deteriorates and the more likely it will cause hard starting, performance issues and gum deposits that clog the fuel system.
If the gasoline in your fuel tank and carburetor has significantly deteriorated during storage, you may need to have the carburetor and other fuel system components serviced or replaced.
Can I use E85 in my Honda Marine Engine?
E85 contains 85% ethanol and must not be used in Honda Marine outboards.
Using fuels with percentages of ethanol or methanol higher than 10% may cause starting and/or performance problems. Such use may also damage metal, rubber, and plastic fuel system components.
How can I tell how much ethanol is in my fuel?
A gasoline/alcohol tester, tool number 07APJ-001A200, is available to determine the percentage of ethanol in a fuel sample. The tester can be ordered from American Honda Parts Department through your local Honda Marine dealer.