With the unprecedented closure of campgrounds in various states and provinces, to curb the spread of Covid-19, questions abound about what should a RVer do to protect the fuel? This question usually arises when the RVer is placing the RV in seasonal storage such as preparing to leave it for the winter, especially in northern, cold states and provinces. Occasionally the question arises when a RV is going to be left in one place for a month or more during a seasonal stay at a RV park or resort in the winter months in the southern states.
My advice is consistent no matter whether it is diesel or gasoline powered: Stabilize the fuel with the appropriate Fuel Stabilizer based on the type of fuel used. Fill the fuel tank, the add the fuel stabilizer before the RV sits for a month or more. The procedure is the same for both diesel powered and gasoline powered RVs.
Fill the Fuel Tank:
By filling the fuel tank, any air that might contain moisture is displaced, so that as the temperature changes that naturally occur, moisture in the air does not condense inside the fuel tank and create numerous problems.
Add the Proper Fuel Stabilizer:
Since both gasoline and diesel fuel are used in modern RVs, select the fuel stabilizer appropriate for RV’s fuel. Diesel Fuel requires a different type than Gasoline. Over the last couple of decades both fuels have been reconstituted to allow the vehicles to comply with emission standards. Leaded gasoline provided lead as a lubricant and stabilizer for short term storage. Lead damages the catalytic converters, that were introduced to allow gasoline engines to attain emissions standards. Gasoline was reformulated without lead, blending more volatile additives into the fuel. This provided the octane needed to give good engine performance and protected the converter from serious damage. However, these additives do not have the longevity that lead used to provide. After sitting for more than thirty days, the fuel becomes ‘stale’. Fuel stabilizer extends the length of time that this fuel can sit in storage and still provide reasonably good performance when burned in newer gasoline engines designed to use unleaded gasoline.
Similarly, in 2007 diesel fuel available in North America was reformulated to almost eliminate the sulfur content and various additives were added to provide the lubrication that sulfur had supplied, which will not harm the diesel emission control systems.
Both fuels became much less stabile when sitting unused for more than a month. The fuel stabilizers required vary with the fuel; there is a specific stabilizer for gasoline, usually colored with a red dye, and another different stabilizer for diesel fuel, usually a lighter brown or tan color.
I have been using both types of stabilizers in the fuel of our RVs for thirty years. The brand that I favor is Gold Eagle’s brand STA-BIL. The gas version has a RED label with WHITE lettering and the Diesel version has a GREEN label with WHITE lettering.
Choose the Storage Concentration:
A caution when adding stabilizer to the tank. On each container are two sets of usage instructions: One is the amount to add when using it as an additive in each tank of fuel. The second is ratio required to provide long term storage. It is this concentration that should be used to stabilize the fuel in the tank when leaving it for a month or longer.
Each bottle has a measuring/dispensing section so that you can easily determine the amount required and simply add it. The primary number required is the capacity of the RV fuel tank so that the amount of stabilizer needed can be added. The design of the bottles is such that it is easy to load the measured section of the container by squeezing the larger side which brings the mixture into the smaller side. Then the tapered end of it is inserted into the fuel filler where the contents flow into the tank. Do this, the number of times necessary to add the proper amount. After the appropriate amount is added, it is best to drive the RV a short distance to mix the stabilizer in the tank with the fuel and to draw the stabilized fuel into the engine injection system. Start the generator (if it is not a propane fueled one) and let it run for a few minutes preferably under load to stabilize the fuel in its fuel system.
Storing the Remaining Stabilizer – A Caution:The remaining stabilizer should not be stored, once opened for more than a year. It is recommended that you mark either the ‘opened’ date (or the best before date) on the container with an indelible marker so that you do not add stale stabilizer to a fuel tank. A sealed container can be kept much longer.