BazerLCGI

Whilst on a family holiday back in August my Chrysler Grand Voyager 3.3 2006 over heated in Germany. I did manage to stop before any damage. The car was taken to a local German garage and they said the water pump was leaking. I found this strange as it was replaced last August. They quoted 400 euros to replace it. I was not happy plus we had already missed the ferry home. The car took 20 days to be repatriated 20/9/16. My local mechanic had already had the new water pump to be fitted. When he inspected the car and filled it with water the engine core plug above the water pump was leaking badly. When I was in Germany they was no water leaking from my car. just a small amount for steam. My question is does any body know the part number for the cylinder core plug? Also found out the company returning the car drove it. Would this cause the core plug to pop if there was no water in the cooling system? Sorry for the long post. Hope someone may know the answer.