This is, unfortunately, the 2nd biggest corrosion issue with the F225's. I had the same problem. The good news is that it can be repaired with J.B.Weld epoxy or similar and it will get you through the striper season - assuming the water spray did not get into the air intake, which based on the location of the hole, i assume it did not. How long the epoxy patch will last is anybodies guess. I repowered shortly after, but i know the motor is still running a few hundred hours later. However, you need to get in there from the inside and see how extensive the damage is- that little hole I can tell you right how is just the exit wound if you will. Once you start cleaning it out from the inside, it will likely get bigger. Just seeing where it is located makes me believe you lucked out a bit there as it's easier to access and patch - most often the hole appears in the bend of the housing right before it meets the block and makes for real PIA repair. If i remember correctly, you can now purchase a replacement housing cover that includes an anode on it and which will help protect the housing. Out of curiosity, is it the counter rotating or the regular rotation motor that is affected? For some reason all the motors that I personally have seen (about 4 of them) had the thermostat corrosion on the counter - started thinking it's not a coincidence. Good luck!
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