Alternator moans before failing? (1 Viewer)

[rkymtnLC]

Think what you will!

My LC 200 y 2000 284k has been low humming,for 2 years but voltmeter showed new battery and old alt doing just fine at 12.+ Cold and 14.+ With engine on...
All the way to this morning!
2 mechanics 2 yrs ago at maintenance said they couldn't hear the low hum nor replicate it?

Today I checked battery and alt w my cheap volt meter again before setting out bc noise much louder in last week and my gut wrenching at it.

Do alternators moan?
Or is that a tensioner not tensing?
Or the pulley not pulling?
Or the S belt slipping?

Or all of the above?

On way home at sunset (and decrease in temp from 65 to 50) after 3 start,/stops sunset, the dreaded battery light came.
It went off when I drove at 2,000 - 3000 rpms. Then On again at lights.

I sped home, turning headlight lights off when could.

Appt next week at Mud recommended mechanic. Fingers crossed!

Q:
Do I replace all of the above: pulley and tension and S belt and alt (and connector)?

Do I keep my OEM and have it rebuilt?
Buy a cheep one?

It's my only driver and winter is setting in.

Thanks all!!

 

[SteveH]

My alternator made no sounds before dying. I saw the 'Batt' light once while driving, and the voltmeter wasn't staying where it should. Testing with the headlights on (engine running) showed poor voltage. I bought a dealer reman for $148 (below list) and installed it and all is well. The aftermarket ones were about the same price, and I would much rather have an OEM Toyota reman.

If the bearings are bad in your alternator, it could be making noise, but you will likely have to just replace the alternator, check all other bearings (tensioners, etc.) nearby, check the belts themselves, re-assemble, and listen for noises and then go further.

 

[rkymtnLC]

Thanks so much for the insight!
The noise has baffled since it was temp sensitive and voltmeter said all Ok until...a few hours ago!

Yes I spent rest of pm looking at alt offerings...Amazon (china?) and Toyota "OEM" and hope/think I found one reman at Toyotaparts and not for $500+. I don't understand how to test/trust quality of reman tho?

I hope the mechanic shop won't be upset that I have the replacement in hand...but ordering now and ready for appt after/bc of holiday will hopefully return car to me faster.

Thanks again for reply and Info.

 

[Eicca]

My mom’s alternator started making a moaning noise and then died a rapid death two days later. Video here: Alternator rebuild kit source? Unsure of what's trustworthy - https://forum.ih8mud.com/threads/alternator-rebuild-kit-source-unsure-of-whats-trustworthy.1322736/

My local Toyota dealer had a reman for $170 plus core.

I also would recommend putting a shield on the new one cuz the power steering is guaranteed to leak right on it.

 

[rkymtnLC]

Ohh great idea on shield. Yes!
Thank you!

I guess I should be grateful that it lasted as long as it did...and that the quiet moan warned me for 2 years... Till it became loud this week!

It feels unsettling to love a car so much...

 

[newbielx470]

In some cases the alternator emits a rubber-burning smell before it goes out. Even if you have windows closed (but AC getting outside air), you can smell it.

 

[rkymtnLC]

In some cases the alternator emits a rubber-burning smell before it goes out. Even if you have windows closed (but AC getting outside air), you can smell it.

Ah ha..yes I wondered what that was over past...2 Years? I thought maybe a belt or tire issue. Mechanics couldn't "replicate'. I guess they didn't drive it?? Oh well.

Still baffled why battery and alt would show all ok y'day morning on volt meter...and battery light on by sunset?

Fwiw I checked battery this a.m. and it was reading 12.2...but I feel it should be towed the 25 miles via highway to new mechanic...I don't want to make things worse...or it die in traffic.!?

Thanks for helping me to understand the telltale smell.

 

[nissanh]

Why do you think the P/S pump is going leak? I never had a leaky P/S pump on any of my toy. The shield can cook the internals of the alternator. There is a built in fan on the armature to cool the alternator but with the shield, there is no room for the hot air to escape.

 

[Wilsil]

The bering on my alternator start making a noise, I reckon I will be in the market for a new one soon.

 

[reconranger]

I had to replace my alternator due to leaking from the power steering pump. On my '06, the power steering pump is right above the alternator. Replaced both.

 

[nissanh]

I would get the leak fixed ASAP before it ruins the alternator.

 

[Gnarwgn]

Similar experience, similar mileage - power steering pump went bad, soaked my alternator, then alternator went bad. Alternator (on both my land cruiser and 4 runner) made an audible 'whine' similar to the sound of my failing power steering pump. Also alternator gets worse in cold weather (mornings/evenings), and yes issue 'disappears' at higher RPMs. Which has something to do with how fast the brushes are/are not moving within the alternator. So you can 'limp along' on a failing alternator if you are on a freeway going 60-70mph, but you start losing it again as soon as you exit. I'd suggest replacing both 'while you are in there.'

 

[2001LC]

I've heard a number of alternator sing/whine, prior to failing. It's difficult to isolate sound, since similar to drive belt or its pulley bearings sound. But, I've found by making sure those others, are not the sound. Then, placing a mechanics stethoscope on a screw/bolt on the back of alternator. You can isolate.

Note: Most alternators I replace. The #1 skid plate is missing.

 

[rkymtnLC]

Similar experience, similar mileage - power steering pump went bad, soaked my alternator, then alternator went bad. Alternator (on both my land cruiser and 4 runner) made an audible 'whine' similar to the sound of my failing power steering pump. Also alternator gets worse in cold weather (mornings/evenings), and yes issue 'disappears' at higher RPMs. Which has something to do with how fast the brushes are/are not moving within the alternator. So you can 'limp along' on a failing alternator if you are on a freeway going 60-70mph, but you start losing it again as soon as you exit. I'd suggest replacing both 'while you are in there.'

Thank you!
It's reassuring to hear of similar experiences and advice bc gives me confidence to work w mechanics after being dissed re specifically this noise ...yet given 2 lists of totally different recommended"fix it's" by each mechanic.

So new questions:
Towing is needed to shop 25 miles away, right? All hwy...and traffic?
Dint want (it) to die en route?
Even if 'just S belt or tensioner'

And

IF it turns out to be "just":tensioner and serpentine belt...
Should Alt be replaced regardless bc
1) it's right there and pia to get to plus
2) it's 183k?

Or just carry my new-to-me reman alt.in back seat?


Thanks everyone for the advice! And experiences...
So grateful.

 

[rkymtnLC]

I've heard a number of alternator sing/whine, prior to failing. It's difficult to isolate sound, since similar to drive belt or its pulley bearings sound. But, I've found by making sure those others, are not the sound. Then, placing a mechanics stethoscope on a screw/bolt on the back of alternator. You can isolate.

Note: Most alternators I replace. The #1 skid plate is missing.

Thanks.. I'll try this.

Exactly the issue of last year and whine.

I saw on YouTube a guy who attached a plastic jug to his screwdriver to act as a megaphone...rather than the "old" trick of screwdriver (into) ear/head.
Seemed a good .

Thanks!

Skid plate?! Ok.

 

[2001LC]

 

[rkymtnLC]

Thanks!

 

[2001LC]

I'm in Centennial near Arapahoe Rd & Colo BLVD. Stop by if you like, I can take a look.

 

[rkymtnLC]

I'm in Centennial near Arapahoe Rd & Colo BLVD. Stop by if you like, I can take a look.

Thanks much--
With car battery light on more than off
I think I'll just let it be towed to shop next...and not press my luck!
Thank you for your kindness tho!

 

[rkymtnLC]

Thanks much--
With car battery light on more than off
I think I'll just let it be towed to shop next...and not press my luck!
Thank you for your kindness tho!

Hi again...I'm sorry I didn't realize you worked on cars as a highly recommended mechanic! As well as being super helpful on this forum! Thanks again for your offer to take a look/listen!

I just went to start car and battery light is still on below 1500 rpm tho it sounds normal (no more moan/whine? Must be temp sensitive) and roars fine at start.

I'll have to have it towed to best be careful But you're on my side of town!

Similar experience, similar mileage - power steering pump went bad, soaked my alternator, then alternator went bad. Alternator (on both my land cruiser and 4 runner) made an audible 'whine' similar to the sound of my failing power steering pump. Also alternator gets worse in cold weather (mornings/evenings), and yes issue 'disappears' at higher RPMs. Which has something to do with how fast the brushes are/are not moving within the alternator. So you can 'limp along' on a failing alternator if you are on a freeway going 60-70mph, but you start losing it again as soon as you exit. I'd suggest replacing both 'while you are in there.'

Thanks so much... exactly!