🔍 Key Concepts

• Effects of sulfur in fuel on combustion byproducts • How sulfur oxides (SOx) interact with moisture to form acids • Which engine parts are directly exposed to hot combustion gases vs. fuel oil itself

💭 Think About

• Think about what sulfur turns into during combustion and whether that product is abrasive, corrosive, or sticky. • Which engine components are in the path of high‑temperature combustion gases where acidic corrosion or wear would be most severe? • Ask yourself: which option describes a problem most commonly linked to acidic corrosion and abrasive wear, not just dirt or varnish?

✅ Before You Answer

• Identify which parts see burned gases (after combustion) versus which see liquid fuel (before combustion). • Decide which damage type fits high‑sulfur fuel: corrosion/chemical wear vs. varnish/soft deposits vs. mechanical blockage. • Eliminate any choices that mainly relate to fuel instability or oxidation rather than sulfur content.