ADDING SEA FOAM MOTOR TREATMENT TO A PARTIAL TANK OF FUEL. Consider the following approximate dosage ratios when adding a full 473mL can of Sea Foam: 60 liters of fuel amounts to 8mL of Sea Foam per liter. 30 liters amounts to 15mL per liter. 15 liters amounts to 30mL per liter.  7 liters amounts to 65mL per liter. One liter of fuel is 1000mL.  When it comes to cleaning dosages, none of the listed Sea Foam ratios is excessive though 15mL per liter is often a sufficient starting point.  Remember that more Sea Foam can be added to fuel when needed, and more fuel can always be added to a partial tank. Our Answer and Recommendation: If you’re adding Sea Foam Motor Treatment to fuel for the purpose of cleaning valves, carburetors, injectors, and chambers, adding more Sea Foam to a partial tank of fuel will offer a higher concentration of petroleum cleaning solvency than the same amount added to a full tank. So, when cleaning a gasoline or diesel fuel system, it’s safe to add as much Sea Foam cleaning solvency to fuel as you need.  For overcoming driveability problems caused by residues and deposits (hard starts, stalls, hesitation, loss of power), you can start by adding a full pint of Sea Foam Motor Treatment to a partial tank of fuel. Adding when tank is low maximizes treatment concentration. 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.