An engine comprises a block, a piston, a head, a fuel injector, and a sleeve. The block includes at least one bore. The piston is configured to reciprocate within the bore. The head is coupled to the block and defines with the block and the piston a combustion chamber. The fuel injector is coupled to the head and is configured to deliver fuel to the combustion chamber. The fuel injector includes an actuator extending between a first axial position and a second axial position along a longitudinal axis of the fuel injector. The sleeve is coupled between the head and the fuel injector and extends between a third axial position and a fourth axial position along the axis of the fuel injector. The area between the first and second axial positions at least partially overlaps the area between the third and fourth axial positions.