A drive unit, in particular an internal combustion engine, has a fluid line arrangement, wherein the fluid line arrangement has a cavity accessible for a fluid via a bore in a first wall element. A spacer element for the fluid line arrangement has a resilient clamping sleeve which can be introduced through the bore. The clamping sleeve has a first longitudinal section which is provided so as to remain in the bore in contact with the bore wall and a second longitudinal section which is set back from the first longitudinal section by way of at least one notch which runs transversely with respect to a longitudinal axis of the clamping sleeve. The second longitudinal section is configured as an axially slotted tube which serves as the spacer element, the borders of the slot being bent radially outwards.