Sparky said:The whole thing is aluminum.
Cooztwo said:Steel bolts in contact with the aluminum block will cause intergranular corrosion if an electolyte is present (liquid). This is a severe form of corrosion as it gets into the grains of the metal and exfoliates (turns to a whitish powder).
Cooztwo said:the gaskets and seals used do a good job at keeping the liquid out or in which ever way you want to look at it. I'm sure you'll have traded, sold or otherwise moved on before there is anything to worry about. Most bolts have a coating that prevents or at least inhibits the corrosion process.
Cooztwo said:I didn't notice before but I see you are in Iowa, I'll go out on a limb and say, from a corrosion stand point, that I'd be more worried about the winter salt on the roads than a water pump.
Cooztwo said:Have you read about my issue yet? #2 cylinder wet