Abstract: A combustion chamber comprises an outer wall and an inner wall. The outer wall has mounting apertures extending there-though and the inner wall has threaded studs extending there-from. The threaded studs extend through the mounting apertures in the outer wall. Cooperating nuts locate on the studs. Walls are positioned between the outer wall and the inner wall. Each wall is spaced from and extends around a respective fastener to form a chamber around the respective fastener. Apertures extend through the outer wall. Each aperture is spaced from a respective mounting aperture. Each aperture allows a flow of coolant into the associated chamber and around the associated fastener to cool the fastener. Each wall has an opening at a position diametrically opposite to associated aperture to allow the flow of coolant out of the chamber to a space between the outer wall and the inner wall.