Heavy fuel oils generally have an upper average ash content of 0.1% by weight. Which of the following conditions could be expected if the ash content increases above this amount?

Correct Answer: Option A — Increased exhaust valve wear

Heavy fuel oil ash primarily contains vanadium, sodium, and nickel compounds. When ash levels exceed acceptable thresholds, high-temperature combustion forms hard, corrosive deposits on exhaust valve seating faces, leading to blow-by, localized burning, and accelerated valve seat wear.