The engine has 100km and was overheated few times, the last time totaly - was driven about a mile with temp gauge at max, flushing the coolant throught exhaust :-(

I'm wondering, does it make any sense to rebuild an engine like that? For example, what all parts have to be replaced and can be there be damaged although all replacable parts are replaced?

Thank you for your answers!

 

Overheating results in warping the aluminum rotor housings. If they warp out of spec the coolant o-ring does not last very long. So a rebuild would involve atleast replacing the rotor housings and the side plates have to be checked for warpage also.

 

Yes; it depends on how hot it got. If you have a dial-indicator or a straight-edge, check for warpage. Any amount of warpage will result in at least a weak (power-wise) motor, not to mention leaky water O-Rings and oil consumption problems. In the Haynes manual, it gives a good description of how to spec everything out.