[tmpusfugit]

aluminum, no one is trying to sell you anything. What a number of people have done is try to help you avoid the very high probability of damaging or destroying your engine. Do a search of rebuilt water pump failures here and on Rennlist. You will discover many examples of failed rebuilt pumps. You keep going back to Porsche dealers for your talking points. The average Porsche dealer knows precisely the square root of zero about 928's. Only about 30,000 928's ever came to the USA. That was from 1978 into 1995. Over those 17 years and nearly 300+/- Porsche dealerships the average Porsche dealer ship might see 10 928's a year, some none, and some more. But, there are virtually no Porsche trained 928 mechanics at any dealer ship today that has any real expertise on 928's, 21 years after the last model came off the assembly lines and 38 years after the first. Some of the folks on this forum and Rennlist are the experts on these cars today. Rog100 owns perhaps 20 928's at any time, he is an official Porsche parts seller, a Porsche aficionado par excellence, and he has spent many thousands of $$$ on rebuilt water pumps that "were professionally done and better than new" and he ended up eating a lot of them when they failed. He does know of what he speaks. He has done the research made the experiments, and paid the piper ultimately. But, as my dad used to say "none are as blind as those who refuse to see."