im new to this so be patient. was wonder if getting enough water to engine to cool it. so i took off the cover and removed the water pump case.took out rubber impeller. there is one rubber tooth missing and another thats half gone. im sure this needs replaced. but biggest concern is to me it looks as if the silver case the impeller sets in is not perfectly round. its kinda oval shaped and these rubber teeth are scrunched up in one place. is this the way its supposed to look?