🔍 Key Concepts

• Purpose of fuel injector cooling in heavy fuel oil (HFO) systems • Effects of high temperature on fuel properties and combustion at the injector tip • Typical problems seen on injector nozzles in slow‑speed and medium‑speed diesel engines

💭 Think About

• Think about what happens at the injector tip if it becomes excessively hot while handling heavy fuel oil—how does this affect deposits and spray quality? • Which of the listed problems is most directly reduced by keeping the injector nozzle at a controlled, lower temperature? • Consider which options describe effects mainly controlled by fuel treatment/engine operation versus those directly influenced by local temperature at the nozzle.

✅ Before You Answer

• Identify which answer choices are clearly related to temperature‑dependent phenomena right at the nozzle tip. • Eliminate any options that more strongly depend on fuel quality, cylinder conditions, or overall combustion timing rather than on nozzle cooling itself. • Ask: cooling the injector mainly helps prevent what kind of heat‑related damage or buildup at the nozzle?