Question

During overhaul, the disassembled parts of an engine are usually degreased with some form of mineral spirits solvent rather than water-mixed degreasers primarily because_________.

Answer 1

Mineral spirits are used to degrease engine parts during an overhaul because they dissolve nonpolar substances effectively and evaporate quickly, preventing moisture-related damage.

Step-by-step explanation:

During overhaul, the disassembled parts of an engine are usually degreased with some form of mineral spirits solvent rather than water-mixed degreasers primarily because mineral spirits are nonpolar solvents which are more effective at dissolving the nonpolar substances such as oils, greases, and waxes that are typically found in engine buildup. Water-mixed degreasers, which are often polar, are not as effective at breaking down these nonpolar contaminants. Moreover, mineral spirits solvent evaporates quickly without leaving moisture, which could cause corrosion or other damage to engine parts during the reassembly process.

Engine oils, which are largely hydrocarbon chains, are nonpolar liquids and their viscosity changes with temperature. Mineral spirits effectively disrupt the cohesive forces, such as London dispersion forces, which bind the oil to metal surfaces.