Can't track down noise in accessories!

[Mustang5L5]

I have a noise coming from my accessories. It's like a mild whirring/whining noise. If you guys have seen my Water Pump thread, i remove the belt and spun the pullies by hand and when i came to the water pump. It felt rough and made a noise when it spun. So i replaced the water pump and the noise is still there (the way the pump felt, it needed to be changed anyway)

So to confirm, i took my belt off and ran the car for 5 seconds and the noise went away.

So i'm spinning everything by hand with the belt off and can't find it at all. Everything spins smooth. The two idler pullies spin fine although 1 has more resistance to it than the other one. Everything else spins smooth.

I'm about to go try spraying some WD-40 at the pulleys to see if i can quiet it up or change the sound (esp if it's the ilder pulleys)

Does anyone have any other tricks to tracking this down? It's loud enough that i can hear it with the hood shut from across the street!

 

[V_Eight]

Use a pipe or stethoscope. It's there somewhere, you just need to check piece by piece.

 

[Mustang5L5]

Ok well WD-40 didn't do anything.

With the engine running, i used a screwdriver and felt vibration from the alternator. I also detected a faint burning smell and after i turned the engine off, i smelled the alt and it seemed like that was the source. It's also loudest when the engine is cold and gets quieter as it warms up

I'd replace the alt, but i don't want to be throwing money at the problem seeing as i just changed the water pump thinking that was the cause.

I had good reason to change the water pump though...listen to it

YouTube - Failing Mustang 4.6L Waterpump


I have a vid of the sound i'll post in a second

 

[Mustang5L5]

Here's the noise. It's louder than the video shows. It's the whirring noise you hear when i rev. It's loud enough at startup to hear clear across the street. When i shot the vid, the engine was warm, so it was a little quieter

I'm starting to think it's the alt

http://www.youtube.com/watch?v=1x1o0_caYks

 

[V_Eight]

I say replace the alternator with a used one if you don't want to spend top dollar on fixing the noise.

 

[Mustang5L5]

That's just it. I don't mind spending the $$$ on a brand new Ford alt. I just don't want to buy one for the hell of it and it be something else.

I'm trying to make sure. I'm gonna take the alt to AZ and have them bench test it and see if i hear the noise when they spin it up on their stand.

Otherwise i'll look to borrow an alt to try it out.

 

[V_Eight]

That's just it. I don't mind spending the $$$ on a brand new Ford alt. I just don't want to buy one for the hell of it and it be something else.

I'm trying to make sure. I'm gonna take the alt to AZ and have them bench test it and see if i hear the noise when they spin it up on their stand.

Otherwise i'll look to borrow an alt to try it out.

One thing I've seen a mechanic do when I had a pulley squeak was take a pry bar and start playing with it behind the pulleys while it was running. I thought he was nuts, but he quickly found out it was the tensioner. Food for thought!

 

[CobraRed_96_GT]

Tensioner is rather common, i had to replace mine. But it's more like a squeak and hapens most often when the engine is cold. Just tell people it's blower whine

 

[V_Eight]

Tensioner is rather common, i had to replace mine. But it's more like a squeak and hapens most often when the engine is cold. Just tell people it's blower whine

Quiet ass blower then! Must be an SQ!

 

[Mustang5L5]

I'm just concerned about the slight burning smell coming from my alt.

It's not stong, but it's there

 

[LaserSVT]

I'm just concerned about the slight burning smell coming from my alt.

It's not stong, but it's there

Mike, I was gonna suggest replacing the alt when i read the thread title. I havent seen the problem too much with new edge cars but I have seen 4 different Aero Stangs make a noise similar to what you are talking about and three of them were accompanied by the burnt alt smell. But in all 4 cases the new alt cured the problem

 

[CobraRed_96_GT]

take it to autozone and they'll wheel out a cart to test the alt. If it's making noise im sure the test will show it's not 100% up to snuff.

 

[spederman]

Here's the noise. It's louder than the video shows. It's the whirring noise you hear when i rev. It's loud enough at startup to hear clear across the street. When i shot the vid, the engine was warm, so it was a little quieter

I'm starting to think it's the alt

YouTube - What's this noise?

Hey, thats exactly the same noise mine made when my alt went bad. I had no idea what it was, thought it was my supercharger or idler going bad and then a week later, my car died.

 

[Mustang5L5]

Well, i just pulled the alt out. I'll take it to AZ in the am to test.

It does have a little soot/burn on the impeller and some of the fins, but unsure if that's from the belt.

Thing is...I remembered it's been making this noise for a while. Only recently did it get loud enough for me to notice it. Since i changed the WP, it quieted down to the level it was at before, but not i'm aware of it and want to fix it before i get stranded somewhere. I'd say this noise has been present for at least all summer long because I remember hearing it when i start my car in the AM ever since it has been "windows down" weather.

But just last week, it got louder. I changed the WP and it's quieter...although could be a huge coincidence.

Either way, i got a new Ford Water pump and fresh coolant...and prob soon a new Ford alt

I can't complain. My car is 6 years old and this is the first issue ever

 

[Mustang5L5]

Just an update

It was the alternator.


Got a new Ford OEM alt, put it in. Noise and burning smell gone.

 

[LaserSVT]

*doing the I told ya so dance*

 

[Mustang5L5]

Where were you when i changed my water pump for no reason???



I'm lucky both jobs were cake. I swapped alts in less than 10 mins. Didn't even need to change out of my good work clothes