I bought 3 replacement pistons from ebay to replace two that looked like this on one side

and one that is completely unusable.

Two of the pistons were correct and for the LH side. One of them was a RH side piston that is now installed on the LH side. I did not notice a difference until I saw that the letters were upside down compared to the other three pistons. The bump on the con-rod is correctly oriented for all pistons and the 7 other pistons are on the correct side.

The rave says that the orientation matters because the gudgeon pin is offset.


How much does this matter? What will happen if I leave that piston in? Can the piston be taken off the con-rod and put in the opposite direction? Can I do this myself, or can only a machine shop remove the gudgeon pin? Maybe the original piston would work?

 

I took it to the machine shop and he installed the piston the other way around on the connecting rod.