Help diagnose a rattle?

I recently replaced my alternator and after I put it back together I have a rattle. I'm about to take it apart again. I double checked torque on everything and the alternator is now working. No codes.

Bad pulley? I replaced them in December.

Here is the video

I figured I'd ask now before I take it apart again.

Sounds like the alternator clutch mechanism to me. At WOT the clutch disengages. Perhaps a lose connection whereby the clutch is intermittently engaging and disengaging.

https://www.m3post.com/forums/showthread.php?p=22438822&highlight=clutch#post22438822

DrFerry wrote

Sounds like the alternator clutch mechanism to me. At WOT the clutch disengages. Perhaps a lose connection whereby the clutch is intermittently engaging and disengaging.

https://www.m3post.com/forums/showthread.php?p=22438822&highlight=clutch#post22438822

Alternator is brand new Valeo. Just installed it.

Sound is coming from the PS pump I think, at least that's where I hear it with a stethoscope.

Really confused at this point. Odd coincidence that the PS pump would do this with an alternator replacement. I didn't touch that side of the belts, pulleys etc.

Sounds like a bearing on its way out. Hopefully just an idler/tensioner.

Better video.

It almost sounds like something lose or like broke off and bouncing around... if it's new than I doubt it's just the new alt....

Maybe to just rule it out place old one back in and see if it still rattles?

Mimmer wrote

It almost sounds like something lose or like broke off and bouncing around... if it's new than I doubt it's just the new alt....

Maybe to just rule it out place old one back in and see if it still rattles?

Yeah like a bushing is missing or a mounting bolt and washer isn't tight or too long.

I found the problem, a bolt in the bracket the alternator mounts to backed out.

The last rib of the pulley was worn down by the bolt.

Plan is to use some loctite and reinstall the bolt. I am ordering a new PS pump pulley.

Is the pulley okay to use while I wait for the new one? I have sanded it and it's very smooth.