6I0284 Inner Valve Spring Fits Caterpillar Industrial Construction ModelsOne New Aftermarket Replacement Inner Valve Spring Fits Caterpillar (Fits CAT) Industrial and Construction Engines This aftermarket replacement inner valve spring fits the intake and exhaust valves on Fits Caterpillar 3054 and 3056 diesel engines, as well as their Perkins engine equivalents. The 3054 and 3056 are inline four and inline six cylinder industrial diesel engines used across a wide range of Fits CAT construction and material handling