serpentine tensioner

[rfuree11]

I posted in stock 95-01, but it wasnt going to be seen, so im posting here instead

So I had a horrible rattling coming from under my hood and it seemed to be coming from the alternator (I didnt even think about the belt tensioner, as it was only two years old), I replaced it and still had the noise and noticed that the belt tensioer was jumping all over the place. I went to napa and got a new tensioner and still have the noise and the new tensioner is also jumping all over the place. I know it was a crappy design from ford, but is there anything else that would cause it to jump around and rattle like that? I know its not the alternator because I have done every combo of new and old alternators and new and old tensioners and still can't get rid of the rattle.


and heres a video of the damn noise: http://www.explorerforum.com/files/10517/dscf0080.avi

 

[BeauJ]

I had a problem with my idler pulley and thought it was the tensioner. Is it squealing? I could try to be more help, but the link to the vid doesn't work.

 

[rfuree11]

No, no squealing and the rattling isnt as bad with the new tensioner, so I dont know whats up.

It really does sound like its coming directly from the alternator, but the tensioner is jumping around like crazy

the video should work now

 

[trucku]

I second that... The idler pulley is cheap too. When you have the belt off, go ahead and rotate all the pulleys to see if one of them is binding some how.
Good Luck

 

[rfuree11]

the idler pulley is as smooth as butta

 

[rfuree11]

well, i just swapped alternators, so now im going to go to autozone and return the new alternator and see if i can get another tensioner pulley there and see if maybe the one napa sold me was just a piece of ****

 

[Rhett]

that is very possible. I have gotten "new"? tensioners before and they were noisier than the old one. Sometimes they break in and get quiet after a few weeks though.

 

[rfuree11]

i just put on a new tensioner and its still making the noise

what are the odds that i got a bad alternator thats making the exact sound my old one was making?

 

[goliath]

water pump is fragged and about to seize It has proablly caused the belt to stretch causing the tensioner to bottom out then bounce back to normal causing the bouncing tensioner issue. i just did the same song and dance as you, replacing everything you did, and finally when i spun the water pump by hand it rattled like crazy and i could move the pulley a little too. replaced the pump and its as good as new.

lates
-joshua

 

[rfuree11]

nope- doesnt seem to be the water pump...i gave it a good spin and it didnt make any noise.

I probably shouild have mentioned before that this noise only really happens when its under electrical load. If i start it and it doesnt make the noise, all i have to do is put it in gear, turn the fan on, turn on my headlights, radio, piaas and cb. it comes around somewhere in there.

 

[goliath]

spin the hell out of every accessory by hand. with that level of noise you will easily find your noisy accessory. it could be as simple as a defective alternator, or a stretched belt causing the tensioner dance and the noise.(it is quiet running without the belt right?)

-later
joshua

 

[rfuree11]

spin the hell out of every accessory by hand. with that level of noise you will easily find your noisy accessory. it could be as simple as a defective alternator, or a stretched belt causing the tensioner dance and the noise.(it is quiet running without the belt right?)

-later
joshua

****, i didnt even think of that....i have a new belt chillin in the garage...im going to try that, even though i dont thin kthats the problem

all the accessories spin smoothly...including the alternator.

 

[goliath]

all the accessories spin smoothly...including the alternator.

and the idler pulley, and the pulley on the tensioner - right?

-joshua

 

[rfuree11]

the idler pulley is as smooth as butta

and i'm on the third tensioner...all three spin smoothly

 

[Rhett]

Ok. Here is another thing I have seen happen re: belt noise. The accessory (in this case, the alternator) can be misaligned, and if it has a bracket, the bracket could be out of position. Or the bracket is misaligned/warped. A bad pulley (bearing) is one thing. But the pulleys themselves have to be in the correct position. Being off just a little can cause noise.

 

[rfuree11]

Ok. Here is another thing I have seen happen re: belt noise. The accessory (in this case, the alternator) can be misaligned, and if it has a bracket, the bracket could be out of position. Or the bracket is misaligned/warped. A bad pulley (bearing) is one thing. But the pulleys themselves have to be in the correct position. Being off just a little can cause noise.

i dont think its that because it only happens under electrical load at low rpms. i'm going now to get another alternator (i'm hoping it was just a freak thing where i got another bad alternator) and if that doesnt fix it, its off to the shop.

edit: ive also fiddled around with the alignment of the alternator and it did nothing

 

[trucku]

I had plenty of belt noise ( squeel ) when I started truck. Everything was in line. I changed belt and used some sand paper to take the glaze off of the waterpump/clutch fan pulley where the back of belt contacts. It was very shiny. Oh yeah I also ran into a problem when buying the belt. It fit fine but, it was the wrong length. This led to my tensioner pulley rubbing on radiator hose. I measured the stock belt and found it needed to be 1 inch shorter. Once I got the right belt length the tensioner was clear.

 

[Blee1099]

Sounds like the tensioner to me but can we get another sound clip from engine off to you cranking on it? Make sure you have the AC off just in case.

 

[trucku]

Can't you start the engine with the Serpentine belt of to make sure its not the engine?
You should be able to run it for a 40 secs or so without worry of overheating or anything.

Can't be timing chain whacking around?..2 cents...lol

 

[rfuree11]

http://www.explorerforum.com/files/10517/dscf0083.avi

here is me starting it, putting it in gear, turning on the headlights, turning on the piaas (heres where the rattle starts alittle bit), turning on my cb (here the rattle gets a little worse), turning on the AC...this is where the rattle gets bad and then around the 49 second mark you can really hear it going and then wind down as i turn off the accessories. It doesnt make this noise if i dont have any electrical things on. The tensioner is brand new. I think my plan now is to go get another alternator and see if maybe the other one i got was just a defective unit making the same noise,