The component identified as item #15 is used...

🔍 Key Concepts

• Identify what part of the fuel pump train item #15 is mechanically connected to (cam, follower, or fuel passages). • Understand the purpose of a relieving / lifting lever on large diesel fuel pumps. • Differentiate between components used for priming versus those used for timing adjustment or pressure testing.

💭 Think About

• Trace visually what happens if you move the long external lever (item #15). Which internal part would it move first? • Ask yourself: does this lever seem connected to the high‑pressure fuel line, the injector, or to the cam/follower mechanism at the bottom of the pump? • Consider: on a test stand, what simple manual action would you need often—changing timing, removing air, or temporarily disconnecting the follower from the cam? Why?

✅ Before You Answer

• Verify whether item #15 is linked to any fuel passages or pump elements (if not, it probably does not prime or test pressure). • Check if item #15 operates through a shaft into item #17 and then up/down on the tappet or follower area near the cam. • Confirm that no part of item #15 connects to the injector nozzle or high‑pressure outlet, which would be necessary for popping‑pressure testing.

The component identified as item #15 is used to __________. See illustration MO-0016.

test injector popping pressure

prime the pump to remove air

advance fuel pump timing

lift the follower off the cam

🔍 Key Concepts

💭 Think About

✅ Before You Answer