A static seal includes first and second spaced apart walls having a gap therebetween for channeling a pressurized fluid. The first wall includes a recessed seat facing the second wall defined by spaced apart first and second faces joined together at a base. A seal insert is loosely disposed in the seat and is trapped therein by the first and second faces. The first and second faces are shorter than the insert to project a top of the insert above the seat and below the second wall for initially promoting flow of the fluid over the insert top to deploy the insert in abutting contact with both the second face and the second wall to seal the gap.