Pumps 547961 Oil Fill Cap with O-Ring Seal. (70) $16.62 New. Steel Dragon Tools 4000 PSI 200' Black Powder Coated Pressure Washer Hose Reel (MD-PHR-4000-200) Pump Pressure Washer 45690 Oil Filler Replace Cap With O-ring 2dx. (1) Ryobi 2 Pack Of Genuine OEM Replacement O-Rings # 570742071-2PK.