WARNING: This page is about a different car, the 2020 Buick Regal and 2019 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
Courtesy of GENERAL MOTORS COMPANY
Callout
Component Name
1
Water Pump Inlet Pipe Bolt
2
Water Pump Inlet Pipe Bolt [2x]
3
Water Pump Inlet Pipe
4
Water Inlet Seal Procedure Remove and DISCARD the seal.