Superior Millennium Cylinders May be Affected by Bad Intake Valves - Replacement Required! 

Owners of recently overhauled or repaired Continental 470-, 520- and 550-series engines should be on the lookout for the use of Superior Millennium Cylinders after the firm published a Mandatory Service Bulletin.

The issue lies with Superior brand intake valves, which have been found to be at risk of failure. The affected units have Superior Part Number SA539988, and were shipped between January 20, 2020, and February 23, 2022. The intake valves were used in both new Superior Millennium Cylinders and rebuilt or overhauled cylinders throughout this year, affecting the aforementioned Continental engines. 

 “We have found three instances where the valves have failed in service,” stated Bill Ross, VP of Product Support for Superior Air Parts. “Our overriding priority is always the safety of our customers and their aircraft. Therefore, after the required inspection, should an owner find that their aircraft has the affected intake valves installed, the aircraft is to be immediately grounded until the impacted cylinders can be replaced.” 

While undoubtedly inconvenient, Ross stressed the importance of contacting any shops involved in an overhaul of such engines - it's hard to be sure what parts were used in work done by 3rd-party cylinder repair facilities. Owners will have to affirm that the intake valves used in their rebuild are either not a Superior-branded part, or were manufactured outside of the affected serial range. 

FMI: www.superiorairparts.com