WTF? Scratching noise?

[Volf]

Okay so I thought I found the culprit of the scratching noise I had going on in my car. I thought it to be the alternator. I would stick my head in the engine bay at several spots and I crudely "triangulated" that it was coming from the area of the alternator, then I just listened very intently and used the "screwdriver" method and listened to the housing of the alternator. And decided that it was making the scratching noise. No big deal.

I had the Bosch 80amp alternator and I upgraded and installed the 140amp Bosch this weekend (re-manufactured/rebuilt). bolted up just fine, no problems. The old 80amp would make a light scratching noise when I spun it by hand after I took it out so I patted myself on the back for being so smart :help

Also note that when I spun the "new" 140amp Bosch it was silent.


I started the car up afterwards and all was silent and I continued to pat myself on the back.


WELL NOW ITS EFFIN' BACK!!!!!!! On the new one! WTF? What the hell could be making this noise? It came w/ a new pulley and everything. Nothing on the old alternator was re-used. Any ideas?

[dannydoo]

tensioner pully or another pully prlly
spray some belt dressing on it and see if it stops.
take the belt off and spin the rest of the pullys

[Volf]

Bumping this thread because I'm gonna re-tackle it again.

To update, the little bit of attention I've given this problem has included replacing the deflection pulley and the A/C belt tensioner pulley. It still makes the scratching noise. I'm gonna replace the accessory belt tensioner tomorrow and see what happens.

Any other thoughts for tomorrow?

[Balthazarr]

The belt is scraping something?
YOu can try increasing and decreasing the tension with an allen wrench, but I would be very careful of the fan.
Maybe even remove it. It's not going to hurt anything for a minute or two.

You ought to be like me; deaf in one ear and 25% hearing loss in my other. Then the noises like this won't bother you. :laugh

[Volf]

No, I don't think the belt is scraping something. It sounds like a metal on metal scratching noise. Which makes me think its one of the bearings on the tensioner/deflection pullies. I've replaced all but one of them. Hopefully it isn't a bearing on something important.