Which component's function is critically impacted by thermal decomposition of oil?

The thermal decomposition of oil primarily affects cylinder fins because these components are designed to help dissipate heat away from the engine. When oil undergoes thermal decomposition, it can lose its lubricating properties and form carbon deposits, sludge, or other byproducts that can impede the effectiveness of the cooling process.

Cylinder fins, often found on the external surface of the engine cylinder, rely on a proper flow of air and the presence of effective lubrication to maintain optimal operating temperatures. When the thermal properties of the oil are compromised, heat transfer is less efficient, which can lead to overheating and could potentially damage both the cylinder and the engine as a whole. Proper lubrication is essential for maintaining the integrity of cylinder fins, and if the oil has decomposed, this can impact the cooling effect, resulting in increased thermal stress on the engine components.