Profile: QualCast, LLC specializes in valves, engines and valve seat inserts. Our product line includes valve guides, valve steam seals, water pumps, valve springs and bulk expansion plugs. Our plugs are made up of steels in a wide variety of cup designs. These plugs are used in marine and heavy duty applications. Our new water pump guides are featured with better bearings, precision machined steel shafts, new unitized seals and computer controlled press fitted hubs.