User

My Webasto forced-air furnace would never run properly on #2 diesel. It would run great on kerosene (also called stove oil), which I would lug to the boat in 20 gal cans. Not a fun job when you live aboard. I changed the Webasto to their DW2010 hot water system and now it runs fine on diesel. I have about 80 Gal. of Kerosene/stove Oil left over. Is it OK to put this in with my diesel tanks? My engines are 671 Detroits.

Roy Warner

MV Ocean Bear

North Vancouver, BC

Thanks for posing this question Roy, it's not an uncommon one.  In short, no, I would not recommend using kerosene or stove oil for your diesel engines unless you intended to operate in very cold climates (the fuel would have to remain cold, as in below freezing).  Diesel fuel, often referred to in the industry as number two diesel or D2, is formulated to be used under “average”, at or above freezing climate conditions.  When the temperature drops below this region, #2 tends to gel or wax, which can cause fuel filters to become clogged with wax crystals.  This problem is avoided by using either straight number one diesel or D1 or by diluting D2 with D1.  The problem is, D1, which is essentially kerosene, is thinner and has less lubricity than D2.  That’s not a problem provided the engine is running in cold conditions, however, if D1 is used in a warmer environment, it can cause abnormal wear as a result of its thinner constitution.  Additionally, kerosene or stove oil is not designed to be burned in an internal combustion engine and thus its cetane, flash point and other vital statistics are unknowns and thus not worth risking in your valuable diesel engines.

Steve D’Antonio

PMM Technical Editor