TWO RECOMMENDATIONS: Our MAINTENANCE Recommendation: By maintenance, we mean to maintain a healthy engine or when stabilizing stored fuel. Sea Foam’s maintenance recommendation for all fuel types is 10mL per liter poured into your tank. One can treats up to 31 liters. Our CLEANING Recommendation: When cleaning a gasoline or diesel fuel system, it’s safe to add more Sea Foam cleaning solvency to fuel. In fact, the more Sea Foam you add to fuel, the better it cleans!  Start with a 15mL per liter treatment and increase as needed. Ratios for induction cleaning devices can be as high as 50% Sea Foam to fuel. Additional: Sea Foam is made from highly-refined petroleum and cannot cause harm to an engine. Remember that Sea Foam in your tank at all times is always cleaning and lubricating the entire fuel system! When cleaning gasoline intakes, use in cooperation with Sea Foam Spray Top Engine Cleaner & Lube.