A couple of weeks ago I replaced the water pump on my 2000 2.7 with 5-speed manual. While the serpentine belt was off I inspected the pulleys and found one idler pulley loose. So I replaced both idler pulleys and the tensioner pulley. I then installed a new serpentine belt and fired the car for the first time. I immediately heard an abnormal clicking sound coming from the accessory drive area. Since the access panel was off it was easy to determine the noise was coming from the alternator pulley.
I wasn't able to find much information on this forum about the alternator pulley so I'm posting this to hopefully help someone in the future. I was able to find one informative thread on Renntech with some great help and pictures from ToolPants (thanks ToolPants) and JFP in PA provided the proper torque value for me (thanks again JFP) which is 59 +- 5 ft. lbs.
I'm not positive about exactly what year models used which pulleys so please check for yourself, but I believe in 2000 Porsche introduced the free-wheel alternator pulley used on my car. In addition, I believe some, if not all of the Tip cars continued coming with fixed alternator pulleys while the 5-speed and 6-speed manuals used the free-wheel alternator pulley.
If you are not familiar with a free-wheel alternator pulley (I wasn't) it allows the alternator to free-wheel at times with a clutch like mechanism built into the pulley. Of course the more complicated pulley is probably more likely to fail, as mine did. The other tricky thing is you have to use a special tool to remove and install these pulleys. This tool uses an XZN 12-point socket to engage and hold stationary the center of the alternator shaft and a 31 spline socket to tighten or loosen the pulley on or off the shaft.
So I installed the new pulley this evening and everything sounds normal on the front of the engine. Now I can't wait to drive the car. I have a bunch of new parts on it and haven't driven it in more than a month. Tomorrow or this weekend I hope to rack up some miles and check everything out.
Here are some pictures so you can see what I'm talking about. BTW, from what I can tell the free-wheel alternators have a cap covering the center of the pulley (to keep debris away from the clutch mechanism I assume) and the fixed pulleys don't have the cap.
ddb
