To ensure safety and efficiency all Drive Belts should be replaced annually. If a drive belt is thrown from its pulley this indicates a sign of wear on the belt and should be inspected closely. If you are unsure of how to do this or to change your drive belt, then do not hesitate to contact us. Secomak stock a full range of replacement parts for their gas boosters and are constructed in accordance with the recently published British Standard 8487:2007.