What is chewing up my casings?

[Harry]

Hi All,

I am fixing up a 2007 EC125 and the casing around the water pump shaft bearing is all chewed up. There are no witness marks on the water pump gear?

I have a spare EC125 motor and it also has the same scars.

I would like to remedy this before reassembling the motor.

Any help would be appreciated.

Cheers, Harry