On both sides of the piston, the end of the piston pin bore has suffered serious damage. In some places the damage reaches up as far as the ring zone (Fig. 1).
When the piston was removed there was no longer a circlip in the retaining groove. It had jumped out during operation and broken into fragments. Although the second circlip is damaged, it was still installed in its groove when the piston was removed. Due to the lack of retention, the piston pin has wandered outwards during operation towards the cylinder running surface. Clearly the front face of the pin has prolonged contact with the cylinder running surface. As a result, the front face is worn to a convexed shape (Fig. 3). The running pattern of the piston is formed very asymmetrically.
For more information or to ask about any other problems that you may have, please use our contact us page.