Castrol Foam Air Filter Oil has been specially formulated for application to “wet type” foam air filters to four and two stroke engines. Through a carefully designed balance of selected base oils and additives, the product provides excellent performance in preventing airborne dirt and abrasive particles from passing through the fuel intake system into the combustion chamber.


Castrol Foam Air Filter Oil is designed for use in all oiled foam elements.

Features & Benefits

  • Developed to ensure excellent performance for motorcycle filters
  • Tested in both controlled field conditions and bench test procedures according to BSI 1701 (ISO 511)
  • High filtering efficiency for extended filter and engine life
  • Maintains air flow for instant engine response and maximum power output


NOTE: Wear solvent resistant gloves when using Castrol Foam Air Filter Oil.

1. Ensure the foam filter is clean. To clean, wash a dirty filter in solvent (for example, kerosene or distillate) to remove oil and dirt. Squeeze out any remaining solvent carefully, taking care not to damage the foam element

2. Spray Castrol Foam Air Filter Oil liberally to both inside and outside of the clean foam element. Work into the foam until it becomes saturated. Squeeze out the excess oil carefully, taking care not to damage the element. Allow to dry in a well-ventilated area before reassembling to the engine

3. Service the foam air filter regularly in accordance with the manufacturers’ instruction, and particularly when the unit has been used in dusty, dirty operating environments.

NOTE: If the filter is washed with a degreaser and then with water, remove as much water as possible by shaking or squeezing between an absorbent material or leaving to dry, before applying Castrol Foam Air Filter Oil.

Do not apply or mix Castrol Foam Air Filter Oil with any other fluid to the wet type foam air filters otherwise the efficiency of the Castrol product will be impaired.

Always ensure the correct foam air filter oil (as specified by the manufacturer) is used by referring to the operators’ handbook or the Castrol Lubrication Reference Guide.