Cooling System O-ring 27 3X2 4

This is a orange/red o-ring that is used on one of the "Water Connector" (cooling system fitting) on top of the engine.

Photo (74928))

Coolant Connector

The same part is also needed when reinstalling the water pump:

Photo (74964))

K100RS Water Pump Removed

For the water pump, which you would think would be listed in the cooling system section, the part can be found in the engine fiche 11_4695 WATERPUMP/OILPUMP - OIL FILTER.

It's the same part number: 11 11 1460392