Have a 740ti 1988 with what I thought was a reasonably new water pump. Its casting is bright and shiny whereas the rest of the engine has the typical 148k filth on it. The bearing started squeaking intermittently when cold, sounding much like a loose belt in that when you rev the engine it does exactly the same as a belt in pitch. Squirted a bit of silicon spray in the weep hole up top, and it seemed to silence it for now. But should I be prepared to put a new pump on the thing? Is this one of those harmless noises for a B230FT?

Thank you!