A combine harvester including a frame, threshing apparatus, a grain cleaning system, and a feederhouse pivotally mounted to the frame on a transverse lift axis. The feederhouse includes a conveyor for conveying cut crop material from a fore opening to an aft opening. The feederhouse is configured to support a cutting header at its forward end. The grain cleaning system includes a transverse cross-flow fan having a debris screen protecting an air inlet channel. The debris screen is pivotally mounted along a first transverse edge to the frame and along a second transverse edge to the underside of the feederhouse. One of the first transverse edge and second transverse edge is slideably mounted to the frame or feederhouse respectively to permit the feederhouse to be raised and lowered around the lift axis.