The unit shown in the illustration is called...

🔍 Key Concepts

• Look closely at the spring-loaded needle at the lower tip of the unit and the conical nozzle end that would protrude into a combustion space. • Notice the high‑pressure inlet fitting coming in from the side, and how the passage leads down to the tip past a needle‑type valve. • Think about which listed component is designed specifically to deliver fuel into an engine cylinder under high pressure, rather than control air stages or governor oil pressure.

💭 Think About

• Ask yourself: Which of the choices would most likely have a precision nozzle tip and a needle held shut by a strong spring, opening only when pressure is high enough? • Consider where on an engine this part would be installed: Into the cylinder head to interact with combustion, or in some external control system? • Compare each option: Which ones normally look like small valves or ports, and which one is known for spraying something into the combustion space?

✅ Before You Answer

• Verify which component is typically built as a nozzle with a central needle and heavy spring to control opening pressure. • Confirm which choice is part of a diesel engine fuel system rather than an air‑compressor unloader or a governor safety device. • Make sure the function you associate with your chosen component matches what this design would do: hold back high‑pressure fluid until a set pressure, then release it in a fine spray.

The unit shown in the illustration is called a/an __________. See illustration MO-0041.

combustion rod

fuel injector

interstage unloader

governor relief valve

🔍 Key Concepts

💭 Think About

✅ Before You Answer