A fuel system for an engine including a cylinder, a cylinder head having a quill tube bore, and at least, one fuel injector, is provided. The fuel system comprises a common rail, a quill tube, and a connector. The quill tube is configured to connect the common rail to the at least one fuel injector to supply fuel from the common rail, wherein the quill tube is coupled to the cylinder head such that a portion of the quill tube is positioned inside the quill tube bore in the cylinder head defining a coolant jacket therebetween. The connector is configured to couple the quill tube to the cylinder head, and to hold the quill tube inside the quill tube bore. The connector includes at least one through hole configured to allow passage of the coolant to the coolant jacket.