Time for my yearly maintenance question! We now have a little over 300k miles on the brick and something finally wore out.

The alternator quit and removing the brushes revealed they were extremely short and the slip rings had extremely deep grooves so I decided I would just replace with a rebuilt alternator. When swapping pulley and fan from old to new I discovered that although there was a keyway cut into the shaft there was no key present on the old alternator.

Is this something that was "cost-reduced" out as unneeded (beancounters do stuff like that) or did the pulley installer have a really bad hangover and forget to put it in? Should I scrounge one or is it not that big of a deal?

Thanks,

Justin B.