My car started overheating about two weeks ago and the interior heat stopped working. We thought it was the thermostat so we replaced it. While we were adding more antifreeze to the system, we noticed that it was pouring out from the lower part of the water pump, but couldn't get underneath to see if it was leaking elsewhere. We also noticed that the gap between the lower pulley and the engine casing and the gap between the upper pulley and the engine casing was significantly different and that there were metal shavings clinging to the engine casing where the closer pulley was. Am I looking at just a water pump issue, or does it seem like it may be more than that?