Strange alternator sound??

[N8tabasco]

ok

So I pull up into my garage today, put it in park, turned off the radio... was just about to turn off the truck and noticed a weird sound.
It's like the sound when you turn a car that doesnt have enuff power steering fluid in it but not as loud. Wheels straight, it definatly sounded as if it was comming from the alternator.

Has anyone encountered this before? I have never herd that noise unless power steering was low and turning. It's not the normal idle sound for sure.

Checked the PS fluid and its good and full, no steering issues either.

Oh yeah....it a 97 Disco 1 SD around 100k miles


N8

 

[meyersd]

Could be a belt tensioner going south

 

[scott]

wierd sound

I Agree Could Be Your Tesioner,best Would Be To Remove Drive Belt And Check All Pulleys,possible Alt Bearing Or Shorted Diode In Alt Causing This Noise Also,,,,,scott

 

[joey]

A would agree with the tensioner pulley.... easiest way to check though is either use a machanics stethiscope or a long screw driver with handle to the ear. Put end on possible issues and you will hear the problem. Just keep it out of the fan or belt... don't want any darwin awards.

 

[N8tabasco]

Hey thanx for the quick response!

I will check this out hopefully on Sunday when I finally get a day off.



BTW .... I herd once that there is a gm (sorry bout that) alternator that fits perfectly as a replacement. Is this true?

 

[N8tabasco]

A would agree with the tensioner pulley.... easiest way to check though is either use a machanics stethiscope or a long screw driver with handle to the ear. Put end on possible issues and you will hear the problem. Just keep it out of the fan or belt... don't want any darwin awards.

HAHAHAHA! love it!

I will definatly look like an idiot to my neighbors!!! I`ll make sure to have scrubs on.

 

[N8tabasco]

Once I pull the belt tensioner out, how do I know its bad?

or will it be obvious

 

[joey]

You should be able to feel the bearings inside not turning as well as say a new one.... you can also if you know how, remove the bearing, go down to NAPA or similar and buy a new bearing and replace. Cost under $5 or you can buy a new tensioner at a cost of $80 plus dollars.

 

[N8tabasco]

Sweet! Thanks joey!




Turns out, I found the problem. It is a vaccum hose comming off the intake. When the motor is running, the hose is sucking shut and making a loud sucking sound. hahahaha


Why would this be doing that?

First pic is with engine off

Second with engine running

It is the cleanest one in the pic

Disco 1 97'


PS I just did the seafoam treatment last week(if that makes a difference)

 

[joey]

Sounds like the PVC valve is clogged. Not a good thing. IIRC you can change that fairly cheap.

but I would still keep my eye on the tensioner (they do tend to go bad).