An engine component (2, 3) is disposed in front of or behind the vehicle engine with respect to the direction of vehicle travel. The component (2, 3) is covered by a protective shell (10) from an opposite direction from the engine (1). The protective shell (10) is fixed to the engine (1) by brackets (5, 6). Stoppers (11-13) in the protective shell (10) limit the displacement of the protective shell (10) towards the engine (1) from exceeding a predetermined distance. The brackets (5, 6) are provided with deformable members (5, 6A) which deform in response to an impact load applied to the protective shell (10) and guide the protective shell (10) only in a direction towards the engine (1) up to the position which is limited by the stoppers. In this manner, the protective properties of the external components (2, 3) with respect to an impact load is enhanced.