Pistons, such as those from KB Pistons, are designed so they can be used as either a full floating pin or a pressed pin assembly and require the use of spiral retaining locks (Figure 1).

Retaining Ring Installation

To install the retainer (Figure 2), first stretch it to approximately 3/4? by grasping the two ends and stretching it. When used with a pressed pin application the lock rings must not be used! Place the end of the retaining ring in the retaining ring groove and, using a small screwdriver, press the retaining ring in place, moving around the pin hole in a circular pattern to spiral the complete retainer into place.

Retaining Ring Removal

To remove the retaining ring (Figure 3) requires two screwdrivers. Secure the piston with the connecting rod and soft materials to prevent piston or rod damage. Pick the end of the retaining ring out of the groove with a small screwdriver, and with a second small screwdriver spiral the retaining ring clear of the pin hole.

–Tech Tip courtesy of United Engine & Machine Co.