New alternator is whining

[Tj1004]

So I just installed a new alternator from DB electrical and a new Gates serp belt. Fired it up and it’s got a whine now. Wondering if the new belt might be causing it, putting pressure on something maybe? You think I should just throw a new idler pulley and tensioner on it to see if it helps?

Edit: sounds like the power steering pump is whining. Would a new/tighter belt effect that?

 

[Chris]

Is the whine constant or does it go away?

 

[Tj1004]

Seems to be constant. Definitely louder at start up and seems to fade out a bit but it’s still there

 

[Chris]

Seems to be constant. Definitely louder at start up and seems to fade out a bit but it’s still there

Try spraying some WD40 on it or belt dressing and see if it goes away. That's at least where I'd start. Did you get the right size belt?

 

[Tj1004]

It for sure wasn’t there prior to the alternator and belt. It’s a weekend ride for me so I usually fire it up, give it a once over and look/listen before I hit the road. As soon as I replaced those items and fired it up I noticed the new sound.

 

[Tj1004]

Try spraying some WD40 on it or belt dressing and see if it goes away. That's at least where I'd start. Did you get the right size belt?

Gates K060882 is the belt I bought. Went on fine, no struggles

 

[Chris]

Gates K060882 is the belt I bought. Went on fine, no struggles

Sounds like you could potentially be dealing with the tensioner. While the engine is running, get some WD40 and spray it inside the tensioner pulley as it spins. If it goes away, you've found your issue.

 

[LONGJP2]

To prevent getting a lubricant on your belt, use water on the pulley bearing.
It will quiet a squeal to help locate the problem.

 

[SRCustom]

Take a short piece of garden hose or a 3' piece of pipe, and use it like a stethoscope to isolate the noise. If it is indeed the alt, you're going to need another one...

 

[Tj1004]

Update.

Swapped the idler pulley, it was a bit rough but the whine was still present. Put in the old alternator and the whine was gone. Also the new alternator was smoking hot after only 30-45 seconds of idling. Will be returning this one to DB.