Originally Posted by
stefan
After a looong struggle, we were finally able to figure out what's wrong.
It's a manufacturing fault from Picco. The piston does not pinch on the top, but approx. 3 millimeters below the top. This means that when the engine heats up, cpmression is going away completely.
Btw, here is a picture of a JLR user with the same problem.
Look at the light ring around the poston. This is where the piston is sealing against the sleeve and this should happen at the very top of the piston.
Hi Stefan.
It is pretty much normal-all pistons made this way (some of them is closer to the top, some farther), but all of them has taper on the top. It is done to compencate expantion. If it won't be done, then piston when it is hot will be like mushroom. The numbers on piston varies depend of piston materials properties. Belive me-this is not real reason of your problem.