Letter Re: Can I Burn Off Road Diesel Fuel in a Modern Diesel Engine?

James
In the letter from “John in Central New York State’, he says that most late model diesels with electronic ignitions won’t work with off road diesel fuel. Do you know why? Thanks, J.P. in Montana

JWR Replies: I believe that John’s statement was not entirely correct. Most Diesel engines can run just fine on the off road fuel or even home heating oil (called “red diesel”, in England), but they cannot legally do so on public roads in the U.S. and the UK. The formulations of Home Heating Oil, “off road diesel”, and road taxed No. 2 Diesel fuel are virtually identical. The only statutory differences are A.) The dye added to the off road fuel (to prevent cheating on the road tax) and, B.) The Federal standard for ash content, which is slightly higher for off road fuel. (At worst, this might mean that you injectors might become fouled more often.) The very recently mandated reformulation of “ultra low sulfur” diesel (ULSD) fuel in the U.S. actually makes the formulations of home heating fuel and diesel even more similar. (The older diesel formulation had sulfur added to aid in the lubrication of engine components.) In fact, a considerable quantity of home heating oil comes directly from the same production runs as diesel fuel. For all intents and purposes, the only difference is the dye and lack of tax. A reader of SurvivalBlog informed me that both Stanidyne and Delphi produce an electromechanical pump for some on road applications that use an electric eye to read timing. These types of fuel systems cannot be run on dyed fuel. So before you buy a diesel that was made in or after 1989, be sure that the vehicle’s engine does not have a Stanidyne and Delphi electromechanical pump. If you must make a diesel vehicle purchase without knowing for certain what type of fuel pump that they have, to be safe buy only pre 1989-on road engines and pre-2004 off road/marine engines.

If need be, Diesel No. 1 fuel (kerosene) can also be substituted for Diesel No. 2, albeit with less power and at greater expense. According to an Exxon web page, blending a No. 2 diesel fuel with No. 1 diesel (kerosene) is probably the most common approach to dealing with winter operability for diesels. The Exxon site warns: “But, the use of Diesel Fuel No. 1 reduces power and fuel economy, and often is more expensive, so minimizing the amount of No. 1 Fuel in the blend is an important consideration. Another approach to reduce the filter plugging incidence is to use wax-modifying additives. These additives can give operability benefits equivalent to No. 1 Fuel blending without the power and fuel economy losses.”

OBTW, I discuss alternative vehicle fuels (such as as home heating fuel, biodiesel, “greasel”, aviation gasoline, and natural gas “drip” oil condensates) in my recently released non-fiction book Rawles on Retreats and Relocation.