Rick D, here is a quote.
Rick:This was taken from the Cytoculture papers on BioDiesel:"Warranties and Engine Manufacturer EndorsementsMarine diesel engine manufacturers in United States, Europe and Japan have all recognized the growing role of Biodiesel as a viable fuel additive, and in most cases, as a complete alternative fuel (100%). Two of the sponsors of the SUNRIDER expedition of 1992-1994 were the marine diesel engine manufacturers: Mercruiser (inboard/outboard diesel engine) and Yanmar (outboard diesel engines), endorsing Biodiesel as a suitable alternative fuel to power Bryan Peterson?s 28-ft inflatable Zodiac boat around the world. This 35,000 mile adventure remains the most famous and most publicized demonstration of using Biodiesel in marine engines. Over 18,000 gallons of donated soy methyl ester Biodiesel was provided to SUNRIDER at various destination ports and rendezvous locations (including a mid-ocean fuel transfer from a ship). Bryan started out from Pier 39 in San Francisco in 1992 and returned under the Golden Gate bridge on September 8, 1994, powered by 100% soybean Biodiesel. Brian?s last 100 gallons of Biodiesel were donated by CytoCulture when he stopped in Santa Cruz on the final leg up the coast of California. At that point, he remarked, "The Biodiesel works?.No problems."Engine manufacturers in Europe have a long history of supporting the Biodiesel movement, and those that produce marine engines continue to endorse the alternative fuel use in their equipment. Some manufacturers warranty their marine engines for use with 100% Biodiesel for late models or for older engines retrofitted with newer synthetic hoses and gaskets that proved more resistant to the pure methyl esters over extended periods of time. Some prefer to warranty Biodiesel engines on a case by case basis. In the U.S., diesel engine manufacturers generally stand by their warranties as long as the fuel used in their engines meet the ASTM D-975 standards defining fuel for compression ignition engines. All of the B-20 blends of Biodiesel produced in America meet the ASTM D-975 specifications. Contact your engine manufacturer for updates on their acceptance of B-20 blend as an acceptable fuel within the scope of their warranties."