Alternator Going Bad? Please Look

[DANNYDOO]

Today My car died

All the sudden all my dashlights were deaad.I couldnt shut the a/c off,the car was puttering.

I noticed the windows were vry slow going down.THought battery was dead

I pulled over, the car was running rough, then it idled smooth

I thought the battery was looses cause i seen corrosion. So i figured remove the terminal and clean it ,but the car shut right off when I reved the pos terminal

I chraged battery and drove 40miles w/no problem,came home pulled terminal off and it stalld,I did 8 times.

The 9th time, it didnt stall.

Now its charging good.

The battery had alot of corrosions and had bad contact so bad it wouldnt work until i found the right spot,even after cleaning it fully vrrrrrry gooood.

So now the car is charging gr8 and even the correeded battery is giving no problems.

Yes I have the p/s leak. but it is vry light. and this is a new alternatore 3months old

I DID NOT GET ANY low voltage light. or alternator light. WHY???

I had seen water from the a/c dripping close to the alt area on the floor.What is that??? could it have gotten wet,then dried and is now ok?

[jaswood]

Disconneting the battery with the engine running is a really BAD idea.

[DEATH]

Fix your power steering leak or you will be buying another alternator. P.S. Don't ever use the 'Spell Check' option in your posts- it's very entertaining!

[jaswood]

Fix your power steering leak or you will be buying another alternator. P.S. Don't ever use the 'Spell Check' option in your posts- it's very entertaining!

The power steering fluid leak is most definitely not the causative factor for alternator failures.

The early, 92, etc, LS400 alternator slip rings used a very soft copper and that wears away within 100,000 miles or less, leaving the slip ring brushe(s) in contact with the bare metal alternator shaft.

I replaced, fixed, the PS leak twice, after putting it off for too long, prior to the alternator failing as above.

[SRK]

The power steering fluid leak is most definitely not the causative factor for alternator failures.

Claiming around here that power steering pump leaks DON'T cause alternator failures is going to be a tough sell.....I wish you luck.

[jaswood]

Yes, I know. But my personal experience with 3 LS400's was that the slip rings wore down to the bare metal shaft. ALL had PS leaks at one time or another and while I didn't disbelieve the common wisdom on the issue I am enough of a cheapskate and "if it ain't broke don't fix it" person that I didn't bother with the alternators until they actually failed.

I suspect it all start as a dealer promoted "urban legend" like replacing the water pump with the timing belt.

Speaking of timing belts, those same 3 LS400's are now over 200,000 miles without the timing belt being changed.

[curiousB]

Your experience may be different but there are about 100 or more cases of PS fluid causing the rotor brushes to wear prematurely on this forum. There are even threads for cockamamie alternator covers instead of fixing the root cause leak. Urban legend...., the facts are quite clear.

As for the TB that is a personal call. It’s also a lot less of a card to play if you are a non interference engine. A snapped belt is just a tow and a day or two inconvenience. On an interference it can be $5k+ and/or a complete write off of the car. So if you have an interference engine and you push the TB to 200k miles it’s not a ringing endorsement of a person’s good judgment.

I changed my water pump when I did my TB to be prudent and because there we signs of seal leakage at the weep hole (the pink antifreeze leave an unmistakable stain). It is an extra $98 for OEM WP or $69 for non OEM. I would say the extra cost is trivial compared to the time and effort to get at the TB.

[jaswood]

Your experience may be different but there are about 100 or more cases of PS fluid causing the rotor brushes to wear prematurely on this forum. There are even threads for cockamamie alternator covers instead of fixing the root cause leak. Urban legend...., the facts are quite clear.

As for the TB that is a personal call. It’s also a lot less of a card to play if you are a non interference engine. A snapped belt is just a tow and a day or two inconvenience. On an interference it can be $5k+ and/or a complete write off of the car. So if you have an interference engine and you push the TB to 200k miles it’s not a ringing endorsement of a person’s good judgment.

I changed my water pump when I did my TB to be prudent and because there we signs of seal leakage at the weep hole (the pink antifreeze leave an unmistakable stain). It is an extra $98 for OEM WP or $69 for non OEM. I would say the extra cost is trivial compared to the time and effort to get at the TB.

".there are about 100.."

And just how many of that 100 ever saw what had actually failed, or would even know, or remember, the difference when told.

I would guess 98 out of 100 simply installed, or had installed, a new one and never opened the old one to see what had actually failed.

Urban legend.

[1990LS400]

And just how many of that 100 ever saw what had actually failed, or would even know, or remember, the difference when told.

An alternator on the 90 LS I owned from new until 2003 failed in the early 1990's due to a fluid leaking from the power steering pump. I've known other people who bought LS400's when they first came out and who also had alternators fail due to PS pump leakage. I'm not understanding why you are doubting the information we are providing.

I've retold the story several times on this forum but here it is again. The alternator failed all at once when I was almost 200 miles from the nearest Lexus dealer. I left my wife with the relatives we were visiting and immediately headed towards the Kansas City Lexus dealer. I made to within 5-10 miles of the dealer on the battery alone by turning off everything electric - radio, HVAC, console mounted phone. When the engine finally died after sputtering for a few miles, I was lucky to coast down the an I-435 exit ramp into a convenience store parking lot.

I've forgotten how many PS pumps I went through in the 13 1/2 years with my 90 LS400 -- I think it was five ... some OEM rebuilt from Lexus, some new Lexus OEM, none were aftermarket.

My 2000 LS400 is still on its original PS pump ... nice!

[curiousB]

"there are about 100.."

And just how many of that 100 ever saw what had actually failed, or would even know, or remember, the difference when told.

I would guess 98 out of 100 simply installed, or had installed, a new one and never opened the old one to see what had actually failed.

Urban legend.

Well correlation in the face of large sample sizes makes a pretty compelling case. Fact; many LS400s with leaking PS pump also have alternator failures. Random mutually exclusive events? Or cause and effect. If it was only one or two complaints then maybe you can be dismissive. At some point thought the volume of the failures and the clear correlation is saying something even if you don't want to hear it.

Anyway make your own opinion. I have a 2004 so don't have a dog in this race.

As my kids say, whateva....

[jaswood]

"there are about 100.."

And just how many of that 100 ever saw what had actually failed, or would even know, or remember, the difference when told.

I would guess 98 out of 100 simply installed, or had installed, a new one and never opened the old one to see what had actually failed.

Urban legend.

Well correlation in the face of large sample sizes makes a pretty compelling case. Fact; many LS400s with leaking PS pump also have alternator failures. Random mutually exclusive events? Or cause and effect. If it was only one or two complaints then maybe you can be dismissive. At some point thought the volume of the failures and the clear correlation is saying something even if you don't want to hear it.

Anyway make your own opinion. I have a 2004 so don't have a dog in this race.

As my kids say, whateva....

A) Fact; Many early model LS400's develop PS leaks.

B) Fact; Early model LS400 alternators have "soft" slip rings.

Direct Correlation...NONE.

[1990LS400]

A) Fact; Many early model LS400's develop PS leaks.

B) Fact; Early model LS400 alternators have "soft" slip rings.

Direct Correlation...NONE.

The alternator failure on my 90 LS400 was a direct cause of the PS pump leaking. The alternator was drenched with PS fluid and both the alternator and the PS pump were replaced at the dealership after the tow truck got it there.

This issue has been discussed on Lexus forums over and over since Lexus forums began. Based on your "opinion" you seem like a "newbie".

[SRK]

The slow PS pump leak on my LS wet the inside of the alternator with ATF. The brushes "softened" somewhat, and I replaced them - $20.00. The slip rings, bearings, and all other parts were fine. They are Denso alternators after all - possibly the best quality alternators in the marketplace. That's all it took to repair the alternator, which had not failed, but was bound to do so as the brushes disintegrated.

Slip rings are normally quite thin, and if you had ever repaired other alternators, like Bosch, or Marchall, or Delco, or Autolite, or Hitachi, you'd know that. But you don't.

You are of course welcome to your opinions, as we all are. You cannot however assume you are correct.

[jaswood]

A) Fact; Many early model LS400's develop PS leaks.

B) Fact; Early model LS400 alternators have "soft" slip rings.

Direct Correlation...NONE.

The alternator failure on my 90 LS400 was a direct cause of the PS pump leaking. The alternator was drenched with PS fluid and both the alternator and the PS pump were replaced at the dealership after the tow truck got it there.

This issue has been discussed on Lexus forums over and over since Lexus forums began. Based on your "opinion" you seem like a "newbie".

Yes, I agree, the PS leak location is such that it drenches the alternator with fluid.

And for quite a long time I accepted everyone's word, posts, that the alterator failures were the result of that drenching.

But not after seeing the cause of 2 alternator failures due to DIY repair.

"..replaced at the dealership.."

So you have no direct evidence of the causative factor for the failure, if there was one. And in point of fact it appears that your alternator didn't fail, it was simply replaced due to having been drenched.

[curiousB]

So you have no direct evidence of the causative factor for the failure, if there was one. And in point of fact it appears that your alternator didn't fail, it was simply replaced due to having been drenched.

You're in the running for "Champion of Lost Causes"

[jaswood]

The slow PS pump leak on my LS wet the inside of the alternator with ATF. The brushes "softened" somewhat, and I replaced them - $20.00. The slip rings, bearings, and all other parts were fine. They are Denso alternators after all - possibly the best quality alternators in the marketplace. That's all it took to repair the alternator, which had not failed, but was bound to do so as the brushes disintegrated.

Slip rings are normally quite thin, and if you had ever repaired other alternators, like Bosch, or Marchall, or Delco, or Autolite, or Hitachi, you'd know that. But you don't.

You are of course welcome to your opinions, as we all are. You cannot however assume you are correct.

"..leak on my LS wet the inside of the alternator with ATF.."

"..Alternator, which had not failed..."

"..the brushes "softened" somewhat,..."

Slip ring brushes, ALL communtating brushes, are intentionally made "soft", compressed carbon/graphite powder, so that they wear out first, not the slip rings or commutator segments.

Perfect example of the "urban legend", no way of actually knowing if the ATF fluid was, would be, a causative factor.

[TA in KC]

jaswood, I've been watching this thread for a while and can't understand why you won't just let it die.

Since joining this forum, I've seen you do nothing but offer condescending answers to other members' questions and make attempts to start arguments with other more established and experienced members. That's not what this forum is for.

We all know that there is abundant, colossal evidence to prove that power steering leaks cause alternator failure in Lexus LS cars. If you want to argue about it, I think you should go somewhere else...

[SRK]

Slip ring brushes, ALL communtating brushes, are intentionally made "soft", compressed carbon/graphite powder, so that they wear out first, not the slip rings or commutator segments.

I cannot imagine that they are made "soft" as Denso alternators that don't get oil on them ( just about every other Japanese car) go hundreds of thousands of kilometers without any service at all.

And by the way, alternators use slip rings, not segmented commutators. Generators and starters use segments, but that's integral to their design. As I said earlier, if you had any real-world experience with these things, you'd know that.

[lexfourcam]

The pump sits right on top of the alternator. So of course when one goes so does the other. Ive had that problem twice on my ls. Mechanic said he replaced the pump but it's still leaking. Good thing I have a lifetime warranty on my autozone one and a one year on my 200 amp. When my leak is fixed I'll put my 200 amp back in for my sound system.

[landar]

jaswood, I've been watching this thread for a while and can't understand why you won't just let it die.

I think he is just playing 'devils advocate'. I have a co-worker who does that. Can be annoying at times but it keeps you thinking and on your toes.

[jaswood]

Slip ring brushes, ALL communtating brushes, are intentionally made "soft", compressed carbon/graphite powder, so that they wear out first, not the slip rings or commutator segments.

I cannot imagine that they are made "soft" as Denso alternators that don't get oil on them ( just about every other Japanese car) go hundreds of thousands of kilometers without any service at all.

And by the way, alternators use slip rings, not segmented commutators. Generators and starters use segments, but that's integral to their design. As I said earlier, if you had any real-world experience with these things, you'd know that.

Just how did you get pass the "not the slip rings" and only see the "or commutator segments", later in the sentence..???

[OldBarney]

Today My car died

All the sudden all my dashlights were deaad.I couldnt shut the a/c off,the car was puttering.

I noticed the windows were vry slow going down.THought battery was dead

I pulled over, the car was running rough, then it idled smooth

I thought the battery was looses cause i seen corrosion. So i figured remove the terminal and clean it ,but the car shut right off when I reved the pos terminal

I chraged battery and drove 40miles w/no problem,came home pulled terminal off and it stalld,I did 8 times.

The 9th time, it didnt stall.

Now its charging good.

The battery had alot of corrosions and had bad contact so bad it wouldnt work until i found the right spot,even after cleaning it fully vrrrrrry gooood.

So now the car is charging gr8 and even the correeded battery is giving no problems.

Yes I have the p/s leak. but it is vry light. and this is a new alternatore 3months old

I DID NOT GET ANY low voltage light. or alternator light. WHY???

I had seen water from the a/c dripping close to the alt area on the floor.What is that??? could it have gotten wet,then dried and is now ok?

[OldBarney]

The positive terminal on the 98 LS must be kept corrosion free.You may use a solution of water and baking soda. I disconnected the battery and disassembled the positive terminal lug and wires and cleaned them completely.This must be done whenever you see any corrosion build up.

Old Barney

[jaswood]

The positive terminal on the 98 LS must be kept corrosion free.You may use a solution of water and baking soda. I disconnected the battery and disassembled the positive terminal lug and wires and cleaned them completely.This must be done whenever you see any corrosion build up.

Old Barney

There is a specialty wire brush "set" available that can be used to burnish the battery posts and battery connectors. Both positive and negative connectors should be removed, cleaned, and burnished on an annual basis. There is also some felt pads/rings that can be installed over each post, under the connectors, to delay the onset of the corrosion.

[Calikid13]

I have a 90 LS400 and same thing have a power steering leak all warning lights came on and when I braked they dimmed and car died. And battery wouldn't hold a charge. Now I'm buying new alternator today but for the 90 is the Denso 210-0170 the best and right one to go with. Cause also says the 210-0274 and 210-0282 fit too. But the 0170 see more. I'm not sure please some advice. Or the Denso W0133- 1602373