Description Thermostat Cap that bolts to the housing, also used on OM603 water pump upgrade. The parts below are required to complete the upgrade: Water Pump - OM606 Water Drain Pipe - OM603/OM606 Water Pump Housing - OM606 Thermostat - OM603/OM606 - 80 Degree Water Pump Housing Gasket - OM606 Water Pump Pulley - OM606
