Water pump

It looks like my water pump is leaking. Hard to tell for sure because it's not making any noises. It it does appear to be leaking out of the bottom side. How many bolts hold this water pump on? Without taking all things apart, I only see 2 bolts and those are behind the pulley. Its a 1999 Silhouette Olds with a 3.4.
On another note, If I change coolant over to the good old fashion green. What could happen? One mechanic is telling to dump the dexcool because he says its eating the gasgets. Another says to keep it. It doesn't corroad the radiator. Any ideals?

IIRC, there are 4 bolts holding the water pump to the block. You will have to remove the pully to get to them. Be sure to loosen the pully bolts with the belt on. Easier that way. It's actually a fairly simple procedure with relatively easy, for this vehicle at least, access. The pumps are also cheap (~$20 aftermarket) so if you think it's leaking, just replace it.

As to the second question, find a better mechanic then the 1st one. Dex-cool doesn't eat gaskets. Poor gasket design is what causes the problems. Dex-cool is phosphate and sillicate free, meaning it's designed not to eat away at metal in your system. Regular antifreeze is not phospahe and sillicate free and, over time, do damage. Stick with Dex-cool or one of the more recent equivilents that are compatible with Dex-cool or the traditional.

Thank you. That makes sense. I'll be taking it apart tomorrow.