🔍 Key Concepts

• Clean fuel vs. dirty/contaminated fuel and how it affects precision parts in pumps and injectors • How sensitive fuel injection components are to small particles and water • Typical causes of wear or sticking in fuel pump and injector assemblies

💭 Think About

• Which of these choices would directly introduce abrasive particles or water into very tight clearances inside pumps and injectors? • Which factor is most likely to affect every part of the fuel system (tanks, filters, pumps, injectors) rather than just one location? • Think about what marine engineers are trained to focus on most when preventing injection system problems: what day‑to‑day routine task addresses this?

✅ Before You Answer

• Compare which option would most quickly damage close-tolerance parts like injector plungers and pump elements. • Consider which problem marine maintenance procedures emphasize preventing with fuel treatment, filtration, and draining. • Ask: which of these is most often controlled by regular bunkering, filtration, and tank maintenance, rather than adjustments or alignment work?