First you'll need to locate the alternator. It's the device above the
oil filter and it's also the device that's on the last pulley (belt
system). In general, the bolt size will be 12".
1. Disconnect the cable from the negative terminal of the battery.
2. Raise the vehicle and support it securely on jack stands.
3. Disconnect the wire harness from the alternator electrical
connection. The wire harness is located below the first cable you
disconnected. It's best removed from underneath the car.
4. loosen the alternator lower mounting bolt.Working from above,loosen
the upper adjustment lockbolt,back off the adjustment bolt,swivel the
alternator toward the engine and then release the drivebelt from the
alternator pulley.
5. Unscrew and remove the alternator upper and lower mounting bolts
and washers,then remove the alternator from its mounting bracket.
The hard part is actually removing the alternator out of the engine
area. It's a very tight fit. As of this post I haven't been able to
remove it yet.
This is the same information I found in one of those do-it-yourself
books. I tweaked it a bit before starting this Google Group. You can
find the original post at the link below.
http://wiki.answers.com/Q/How_do_you_replace_the_alternator_on_a_2001_Hyundai_Elantra