AD 33018850 Diesel Engine Oil Filter for Nilfisk Advance Proterra and RS 501 Riding Sweepers. A cylindrical spin-on engine oil filter for 3-cylinder Kubota engines found in the Nilfisk Advance Proterra and RS 501 outdoor sweepers equipped with this diesel engine (Proterra sweepers equipped with the LPG engine uses AD 33018851 oil filter). Don't forget to replace the diesel engine fuel filter as well (AD 33017252 - Proterra Only). One diesel engine oil filter required per unit. Priced Each. Replaces Nilfisk Advance 330118850. Our Part Number AD 33018850