Definition
The high point, or peak, of a cam lobe. As the camshaft rotates, the cam nose is the part of the lobe that pushes the valve lifter or follower the farthest, producing maximum valve opening in a reciprocating engine.
Plain English
The tip of the bump on a camshaft. When that tip rotates around to the lifter, it pushes the valve all the way open.
Context Anchor
Seen in aircraft engine and ignition-system maintenance when checking cam wear, valve movement, or ignition point opening.
Derivation
Cam comes from an old word meaning a curved or crooked piece. Nose is used in mechanical language to describe the most forward or pointed part of a shape. Together, the cam nose is simply the pointed tip of the cam's curved profile.
Why Pilots Care
Worn cam noses can cause loss of valve lift, leading to reduced engine power and potential valve damage.
Intuition Check
Do not read nose here as the front of the aircraft. In this term, nose means the raised peak of the cam that pushes another part.
Example Sentence 1
When the cam nose contacts the lifter, the intake valve reaches its fully open position.
Example Sentence 2
Excessive clearance at the cam nose can lead to improper valve operation.