Fitting the first of two circlips per piston that keep the piston pin from sliding out. The circlips are little spring wires in the shape of a letter C that snap into groves in the piston pin holes.

These buggers are a pain to get in! One wrong move with the screwdriver and they'll be teleported to some random location in your garage with only a faint "tink-tink" sound to tell you where they are!

Applying a little motor oil to the piston pin to help it slide in.

The pin slides through the piston and the small end of the rod until it stops at the first circlip. After this the second circlip is installed, locking the pin in place.

The opening of the circlip needs to be facing towards the bottom of the piston to ensure that the forces that act on the piston when it changes direction don't tend to work the circlip out of its grove.

Pistons with rods installed, ready for rings.