Been searching with no luck...
Does a water pump make noise when it is going bad? I'm getting a metalic sort of whirling noise (almost like something is banging around) from the front of the engine (617.9??) Temp as been fluctuating at operating recently. Sometime running cool; sometimes around 100. ACC works fine heat, cool when and where it should. No change in engine performance. At first I thought a belt was squealing but eliminated that right away. The noise is not present at idle but starts around 1100rpm and gets louder as rpms increase; sometimes. Other times it is hard to even notice. Regardless, it makes me nervous/curious and I need help diagnosing it, please.

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1969 220D "Berta" RIP
1982 300D turbo 250K