I’m repairing my beloved Geo Metro for sale. The battery light was on. The battery tested ok, but the alternator wasn’t making any power. Here’s why:
This is the alternator. It charges the battery when it is rotated by a belt that goes to the engine. You will notice there is no belt.
Here’s the belt.
That would do it.
It’s super seized from rust, and it broke the belt. The Good Thing about that is that the alternator belt used to squeal like a banshee, and it was *super* annoying. I tried treating the belt, replacing the belt, fixing the alignment on the alternator, all to no avail. After I got the car running again, its smooth, quiet operation (even with a blown head gasket and no coolant in the system) seemed intuitively wrong to me. Now I remember why.
The good news it that I was able to order a replacement from Rock Auto for less than $4, along with replacement plugs for the engine and transmission oil plugs, one of which is badly stripped. In the meantime I’m going to try hitting the alternator with some WD-40 and seeing if I can get it un-seized. If I were keeping the vehicle, I’d just buy another one, but since I intend (not want) to sell it, it makes more sense to try to resurrect this one. If I’m lucky, the original squeal was being caused by the alternator being rusty, and cleaning it off will make it go away. It certainly isn’t good advertising for resale.