With two applications this O-ring 7x1.7 is the most specified part.
This part-list fiche shows all the components that make up the C50cm 2000 (y) Japan Aa01-100 Eop-2 .
Some items from this specific schematic: O Ring, 8 Dia, Plug, Rubber, Gasket Clutch Out (nas), O-ring 7x1.7.