Fix one thing. Get another problem...

[ThreeJs]

Got my waterpump swapped out yesterday and now I think my alternator is acting up.

I do most of my driving during the day so, no headlights. Last week I heard something rattling under the hood while putting up garage sale signs Fri. night. Then it stopped.

I figured out the noise only starts when I am running a full load on the alternator. Lights, max A/C and radio all on.
Turn on light switch...ratting noise. Turn off ...noise stops..
Gotta be the alternator?

 

[WMC99]

Got my waterpump swapped out yesterday and now I think my alternator is acting up.

I do most of my driving during the day so, no headlights. Last week I heard something rattling under the hood while putting up garage sale signs Fri. night. Then it stopped.

I figured out the noise only starts when I am running a full load on the alternator. Lights, max A/C and radio all on.
Turn on light switch...ratting noise. Turn off ...noise stops..
Gotta be the alternator?

Off-hand, I'd say you may be hearing the alt. pulley bearing going out.

 

[boominXplorer]

Belt tensioner I bet

 

[WMC99]

Belt tensioner I bet

Quite possible.

@ ThreeJs ... Find a short length of hose and use it as a stethoscope to isolate the noise. One end to your ear and the other end touching various components like the pulleys and bearings. You should be able to isolate the noise.

 

[ThreeJs]

Find a short length of hose and use it as a stethoscope to isolate the noise. One end to your ear and the other end touching various components like the pulleys and bearings. You should be able to isolate the noise

I used a long screwdriver and it does sound like it's coming from the alternator.

I'll double check the tensioner but I don't think it's that.

 

[swshawaii]

Or remove the belt and check ALL pulleys by hand.

 

[MAS Tequila]

Listen to our Hawaiian brother.

About 2 weeks ago I swore my power steering pump was heading south.

I put my mechanic's stethoscope on the different accessories and would have bet the farm the power steering pump was making the noise I was hearing while driving.

So I dusted off the spare pump I had on the shelf, figured I'd be swapping it out over the weekend.

Guess what happened the following day, the AC started blowing hot!

It's cheap, as in free, to loosen the belt and spin everything to see what is really making the noise.

Me, I'm waiting for parts to come in, with my Mounty in pieces.

 

[ThreeJs]

Belt tensioner I bet

Winner winner......

After being able to check it out during the day I found the tensioner bouncing.
Replaced it this morning and..so far...everything seems good.

 

[boominXplorer]

Sweet, glad you got it figured out. It's the spring inside the body of the tensioner that makes all the noise usually.

 

[ThreeJs]

So. The tensioner needed replacement anyway because it was bouncing a lot.
After driving it yesterday for an hour in 110* heat the noise returned. I think the new added tension put more load on the alternator.
When everything got hot the bearing/bushing allowed the excessive play.
Replaced the alternator and for now all seems well.

The noise after replacing the tensioner and everything good and hot....

 

[Spuddy]

Nice!

And, yes, those tensioners go anyways, and usually trash the belt and assorted vacuum lines when they do.

 

[UtahX]

Yeah, always one thing after another.

 

[96eb96]

The idler pulley on 95-98 OHV is a known failure point if it is original. Seriously, replace it ASAP, takes 5 minutes.. The just fail suddenly. Years back it was quite a common issue. First symptoms are random noises that come and go.

 

[ThreeJs]

gotta laugh. The new reman alternator I just installed stopped charging on the way to work this morning.
Luckily I work at a auto parts store and it only takes 5 min. to pull out the alternator.
Got the warranty replacement installed. Knock on wood. Hope this one lasts more than 2 days......

I had already considered replacing the idler pulley.
Going to look one up tomorrow and probably replace it during my lunch break.
what.. a 3/8 ratchet and a 15mm wrench?

 

[96eb96]

gotta laugh. The new reman alternator I just installed stopped charging on the way to work this morning.
Luckily I work at a auto parts store and it only takes 5 min. to pull out the alternator.
Got the warranty replacement installed. Knock on wood. Hope this one lasts more than 2 days......

I had already considered replacing the idler pulley.
Going to look one up tomorrow and probably replace it during my lunch break.
what.. a 3/8 ratchet and a 15mm wrench?

If the battery light goes on it is because of the alternator spade plug. It don't make good contact with the terminal. I think I had to bend mine with a small screwdriver, no issues since. I think you are right on the wrench size, but it was a while ago.

 

[ThreeJs]

If the battery light goes on it is because of the alternator spade plug. It don't make good contact with the terminal. I think I had to bend mine with a small screwdriver, no issues since. I think you are right on the wrench size, but it was a while ago.

Nah...not the connection. I did double check the connections before removing.

Pulled the alternator and tested it. Only put out 11.4V.

Gotta say..it is good working at an auto parts store when I need something

 

[Spuddy]

It is good to be king.

 

[ThreeJs]

The idler pulley on 95-98 OHV is a known failure point if it is original. Seriously, replace it ASAP, takes 5 minutes.. The just fail suddenly. Years back it was quite a common issue. First symptoms are random noises that come and go.

I picked up a new idler pulley and will install it tomorrow. Better safe than sorry.....