Hi everyone. We are currently replacing our water pump again. We had just replaced the impeller last September and it's already shredded. We have a new impeller, pump body and gaskets. As we were installing them we realized we were missing the waterline seal. Is this necessary? Part number is 26-F694735-1. What does this seal do exactly? And would that have caused our impeller to fail so quickly? Thanks for any input, we are new boaters.