🔍 Key Concepts

• Study how the piston pin is held in place in the illustration, especially the connection to the connecting rod small end. • Review the definitions of full floating, semi-floating, and fixed piston pins in standard diesel engine theory. • Look closely for any locking screw, clamp, or circlip that prevents the pin from moving relative to either the piston or the connecting rod.

💭 Think About

• Does the pin appear free to rotate and move slightly in both the piston bosses and the connecting rod, or is it locked to one of them? • If there is a visible bolt or screw going into the pin, what does that tell you about whether the pin can rotate with the connecting rod or with the piston? • Which piston pin type is defined as being rigidly attached to one member (piston or rod) but free to move in the other?

✅ Before You Answer

• Identify whether the pin has retaining clips at the piston bosses or a locking screw through the rod. • Confirm if there is any way for the pin to slide sideways out of the piston; if not, what is holding it? • Match what you see: pin fixed to one part, free in the other vs pin free in both parts vs pin fixed in both parts before selecting your choice.