US Patent 11401833 Seal oil systems

A gas turbine engine includes a first bearing compartment and a seal assembly within the first bearing compartment that includes a rotatable seal seat, a gutter radially outward of the seal seat and fixed against rotation. The gutter includes a channel on its radially inner face. A second bearing compartment is also included. A scavenge pump is in communication with a first supply line configured to supply the first bearing compartment and a second supply line configured to supply the second bearing compartment. The gutter is in communication with the scavenge pump through a gutter scavenge line. A valve between the scavenge pump and the second supply line is configured to close in response to a dry port event, such that closing the valve stops oil supply to the second supply line, while allowing oil supply to the first supply line.