Harley Fuel Tank Cleaning

Harley fuel tank cleaning (or other motorcycle tanks) can be a simple task given you follow some basic steps. Rust or sludge can be very damaging to your fuel system and should not be left untreated. Severe cases of rust can often lead to the eventual failure (leaking) of the tank, so seek professional help if you believe that your fuel tank is in such bad condition.
The easiest way to clean a gas tank of rust and other contaminants is with Muriatic Acid*. Commonly used for pool cleaning and cement etching, this acid can be found at most pool supply stores or any garage meth lab. However I’d stick with the store and avoid hanging out near crazed meth lab tweakers! Avoid contact with this very corrosive acid by wearing heavy rubber gloves and protective eyewear at minimum.

Only use outdoors since breathing this could be extremely hazardous. As with any chemical read the label and warnings.
Now that you have overcome your fear of handling acid it’s time to clean your Harley’s fuel tank.

1. Start by draining the fuel tank of any remaining gas. Disconnect the fuel line and remove the tank from your bike. Remove the petcock and plug with rubber tubing and heavy duct tape, or anything else that can be used as a plug. Do not use any tubing or your original petcock valve that will be reused. 2. Pre-clean the tank with a 1/2 gallon of gasoline. Cap the tank and agitate by rocking the tank. Dispose of fuel in a proper container. 3. Fill 1/2 the tank with hot water. Now add approximately 1/2 a gallon of Muriatic Acid* and top up the remaining with more hot water. Seal the tank with something other than your original gas cap (acid will lift the chrome). Allow the mixture to sit in the tank for 2 hours. 4. Drain the acid mixture into a proper container and dispose of properly (not down the drain or in the trash!). Rinse your Harley’s tank with water several times, then with gasoline. 5. Install the tank back on your motorcycle and immediately refill with gas. An empty tank is prone to the progression of rust. However if you must store your Harley’s tank follow the directions for Winter Storage with a fuel stabilizer . Drain and rinse again with gasoline after storage. Be sure to check back for future articles on coating your fuel tank to eliminate any future rust or oxidation. Gas tank sealers and additional products for rust removal and coatings can be found at Eastwood Co . * Muriatic acid (aka Hydrochloric Acid) is highly corrosive. Read the warning label carefully. Wear goggles and rubber gloves, and never add water directly to concentrated acid as it will react similar to hot cooking oil. The author and/or this web site is not responsible for damages or injury resulting from the use of such products. Handle with care and at your own risk.
Enjoy the Ride!

Step away from that can of WD-40! Use the right product for the job. You wouldn’t wash your car or Harley with a harsh solvent, so don’t use penetrating oil in place of lubricant or cleaner. WD-40 is a water dispersing penetrating oil originally designed to repel water. Almost 60% of this solution is an aromatic corrosive solvent designed to penetrate metals, with a suspended paraffin lubricant designed to remain upon evaporation. There are rumors that WD-40 will actually eat away at certain metals and rubber, but the fact is that WD-40 is NOT designed to clean fuel tanks or lubricate while in storage.