Interesting Belt Failure

[viper501]

So I'm leaving the office last night and start the car. I immediately hear a loud metallic sound, almost like a bad rod .... :( :eek: Shut the car off and do a visual inspection, as best you can in the dark on a 996. Can't see anything obviously broken so I restart and the same noise. Still can't see anything at first, then I realize that the serpentine belt is shredding itself. Examination revealed that the belt is split down the middle. Pulled out my handy-dandy multitool and cut the half that's off the pulleys so I can get it out of the way. While in there, I notice that the small plastic fitting replaced in September (by the Porsche dealer) is rubbing against the idler pulley at the top of the engine. Hmmmmm ... could this be the cause of the belt shred?

Well, I got it to the independent mechanic that normally services the car. A while later they call to inform me that the alternator bracket is snapped and that the alternator pulley has two small dents in it. After a complete examination, they've discovered that the upper alternator mount was loose (the same bolt hold the above mentioned idler pulley in place), allowing the alternator to pivot and snap the lower mount off. That caused the belt to start walking off of the pulleys, hence the shredding. The alternator pulley has two small dents in it. The piece replaced in September has substantial rub marks on it where it was being rubbed by the idler pulley and the oil filler tube is shredded.

A call to the dealer discovers that the replacement of the part in September required the removal of the idler pulley .... hmmmm ...

Lots of pictures taken and a few parts order ... bracket, oil filler tube, alternator pulley, and a couple other odds and ends ... only problem is that they won't be here for a few days ... Once I figure out how to get the pics out of the camera, I'll post 'em for all to see.

The silver lining is that it doesn't look like its going to be *that* bad. The bracket was only $38.00, can't imagine that the oil filler tube is too bad and the alternator pulley shouldn't be too bad. :P

[Loren]

Hmm... I wonder if you had one of early belts/guides?

Have a look at TSB 10/99 1379 Damaged Drive Belt (dated 1-20-2000).

[viper501]

Hmm... I wonder if you had one of early belts/guides?

Have a look at TSB 10/99 1379 Damaged Drive Belt (dated 1-20-2000).

That doesn't look like the problem point. Maybe these pictures will help.

[RicksCarrera]

Hi

I just finnished a thread titled 'alternator bracket failure'. This may be a similar issue. Good luck

Rick

[viper501]

All fixed. $467 and change split between parts and labor. Most expensive part was new alternator pulley (replaced due to two small dents on the outer surface).