The tappet sleeve with hole for Citroën HY-63/11CV/15CV is an essential engine component that aids in the optimal functioning of the valves. This sleeve ensures smooth movement of the tappet, allowing the valves to open and close at the right times. The hole in the sleeve is crucial for lubrication, helping to minimize wear and extend the engine's lifespan. This part is vital for enthusiasts and mechanics working on classic Citroën models and seeking high-quality spare parts to keep their vehicles in peak condition.