Water won't hurt an alternator or AC/clutch! Don't hit it with a pressure washer so that a jet of water blasts past the bearing seals, but other than that its harmless to an alternator or AC clutch. If you've ever had an AC clutch apart, the electrical wiring (just a magnet coil) is completely encased inside a plastic potting compound. Alternator wiring is entirely magnet wire which is coated and waterproof, and even the exposed brush/sliprings won't be harmed by a little water. Heck, offroaders submerge their alternators routinely, and lots of regular street cars have the alternators down where splash from puddles can get to them.