FWIW, my pump seal died at about 110k. The annoying thing was that the mechanic who fitted the replacement didn't check that a blanking bolt was properly tightened. This unscrewed itself over the next few days and finally resulted in a dramatic loss of coolant on the motorway. I was on my way to a very important meeting and there was no way I could make it on time if I had to wait for a recovery vehicle. Amazingly, and I don't know why I bothered to look, the bolt and the copper washer were balancing on the edge of the tray underneath the engine. Five minutes later I was on my way and made the meeting on time. I still have a small burn scar on my right hand to remind me of my good fortune!
1990 230CE 150k+ UK spec.