Alternator Replacement - A Saga (1 Viewer)

[94SRUNNER]

I have had some poor luck with alternators. By my count I am on my fifth alternator. A bit of history...

First off, my LX is basically stock. Nothing that I can figure would cause an alternator to fail prematurely. No leaking coolant or oil from the engine that would cause failure. The area behind the alternator was and is dry.

In December 2016, what appeared to be the original alternator went out for the first time during my ownership at 137667 miles. Due to a time crunch my only option was an Autozone Duralast unit, which went in with out much issue.

The Autozone Duralast unit went out for the second time, approximately 9 months (9/16/2017) later at 150200 miles. It was under warranty, so I pulled out the bad and swapped it for a replacement Autozone.

The second Autozone Duralast unit went out approximately 10 months (7/15/2018) later at 164400 miles. I did not feel like dealing with an auto parts store reman'd unit. I had a used OEM unit that I had picked up and installed new brushes in. I had it tested at a local alternator shop near me in Dayton and it tested good, so I went with that as my replacement and threw the Autozone unit on the shelf.

This past weekend I had to drive to Pewaukee Lake, Wisconsin to pick up my son from my brothers and the truck ran fantastic. No issues. Started it up yesterday and it was typical symptoms, bad electrical whine and reading low voltage on the dash gauge and ScanGauge. So....after approximately 24 months and at 181104 miles I got to do it all over again.

This time I went with a reman'd Denso unit from Napa. Now I have heard the pros and cons of the reman'd Denso's, but I'll take my chances as I've got the change out time to around 2 hours.

Previously I had removed the alternator out of the bottom. This time, I felt like trying a different method. I pulled it out through the top without removing the upper coolant line or the coolant reservoir. Below how I went about it;

1. Disconnect the battery (10mm)
2. Remove intake tube (10mm)
3. Remove serpentine belt (14mm socket on breaker bar or wrench on tension pulley)
4. Remove 3 bolts that hold power steering pump (14mm deep socket)
5. Disconnect the high pressure line (17mm and 37ft-lb for reinstall) and wrap in rags and place a container of some sort to catch PS fluid. Once the flow has stopped, pull the power steering pump out of the way. I also unbolted the PS reservoir, which allowed me to set the pump back even further. Pull the high pressure line back towards the front of the engine bay and secure with a zip-tie.
6. Unbolt the alternators 12 mm and 14mm nut and 14mm bolt that hold it on
7. Slide alternator forward off mounting stud and turn so you access to the rear connectors. Unbolt the 10mm nut on the power calble and squeeze the connector to release it and pull the connector free.
10. Then, remove the alternator out the through the top. If you orient the alternator correctly you can make it around all of the various plumbing components with little effort.
11. Finally, repeat the process in reverse order to reinstall the alternator then the power steering pump. Once both are bolted and torqued to spec, reinstall the serpentine belt, intake tube and finally the battery.

Note; You may need to spend a little extra time bleeding the power steering system, so have some extra fluid on hand as you may experience spillage with this process....

Using this method, I had everything buttoned up in about 2.5hrs

This link is a good resource;

100 series / lx470 alternator replacement quick tips no pictures

Just did this on my 98 LC so it is fresh in my mind took exactly 3hrs and I'm slow, If anyone has basic tips to add please do... I've done this before but not often enough to "do it without thinking" I should add it helps to have a milk crate to stand on... 1. remove plastic engine cover (10mm...

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[JunkCrzr89]

Autozone unit + Autzone unit + used Denso with new brushes but old bearings and regulator = Imminent plethora of failures.

The reman Denso should be fine, given it has new brushes, bearings, and regulator.

I've only ever pulled the alternator out the bottom. Your description of pulling out the top sounds like more work!

 

[94SRUNNER]

Autozone unit + Autzone unit + used Denso with new brushes but old bearings and regulator = Imminent plethora of failures.

The reman Denso should be fine, given it has new brushes, bearings, and regulator.

I've only ever pulled the alternator out the bottom. Your description of pulling out the top sounds like more work!

Yeah. The Autozone units were a poor choice, but done out of necessity. The Denso reman was also one of necessity. It is what is. Hopefully, it lasts. I am going to be working to rebuild the OEM unit that I just pulled.

Based on my experience, the way I removed it today was easier than my prior methods. As with most things, it is all relative.

 

[BadReligion]

Yeah. The Autozone units were a poor choice, but done out of necessity. The Denso reman was also one of necessity. It is what is. Hopefully, it lasts. I am going to be working to rebuild the OEM unit that I just pulled.

Based on my experience, the way I removed it today was easier than my prior methods. As with most things, it is all relative.

I hope the Denso unit works out! I had my front end opened up for a TB/WP job and ended up changing out the alternator and PS pump on a preventative basis since they were right there. Probably took a few minutes each. I went with an OEM denso reman on the alternator, new OEM on the PS pump. I think you can source new OEM alternators on Partsouq, but could be wrong.

After putting the truck back together, I thought about what would be the easiest way to access them in the future if needed. Good to know you can get them from both the top or bottom. I guess I would go bottom if the coolant system needed a flush, and top if the PS fluid was due for replacement.

 

[94SRUNNER]

I hope the Denso unit works out! I had my front end opened up for a TB/WP job and ended up changing out the alternator and PS pump on a preventative basis since they were right there. Probably took a few minutes each. I went with an OEM denso reman on the alternator, new OEM on the PS pump. I think you can source new OEM alternators on Partsouq, but could be wrong.

After putting the truck back together, I thought about what would be the easiest way to access them in the future if needed. Good to know you can get them from both the top or bottom. I guess I would go bottom if the coolant system needed a flush, and top if the PS fluid was due for replacement.

I hope the Denso works too! My local dealership had a new one for ~$600-650 and a reman for $375, but both a few days out. Like I said above, I went with the Denso reman out of necessity. If the dealer would have had one in the same time frame as NAPA, I would have probably gone with them.

PartSouQ has Part #: 27060-50360 for ~$960 and they are currently unavailable.

 

[LCReunion]

So I literally just finished typing up a step by step R and R for the alternator as I just did it twice this weekend...with help from mudders. I take out the three bolts from the PS pump and that let's it move enough. No line disconnect, or reservoir, or bleeding needed after. I too pull it out the top.
My advantage is my wife also being my co-mechanic(yes I am very lucky). The extra hands makes it much easier.

 

[Ramathorn15]

I'm heading down a similar path. OE went out at bout 150k miles. Got it rebuilt by a reputable shop in town. Lasted about 5k more miles before it went out again. I was in Silverton at HIH9 so an AutoZone duralast new unit was the only option. Ive been running on that one for about 5k miles now without issue. I had the OE rebuilt again by the same shop (lifetime warranty) and keep it in the back now.

I can change it out in about an hour or less. Last time I did it I was in gravel trying to finish in a rush before hitting the trails at HIH. I don't remove anything but the alternator itself and the lower front skid plate. Then I can squeeze it though the bottom.

I saw someone posted a high amp aftermarket alternator recently. I may try that next if I keep having issues. It seems my issues started when I installed the ARB twin.

 

[jerryb]

I haven't seen new bearings in denso rebuilds, nor regulator.
rectifier yes, brushes yes. I do wonder though, and assume now, that rebuilt densos don't automatically come with a list of new stuff.
I have two. My original was not the OEM stock unit at 180k.
What I did was redo the first one while I waited on the second to arrive. By the time it did my first one was redone and better than a rebuilt denso.
I thought that's weird, but at least there's a new rectifier on it and brushes. But old reg and old back bearing. Also old brush holder.
Oh well I guess.
My only concern about mine is the non oem regulator. BUT it's been great for at least 35k miles.

I wouldn't just install a new rebuilt denso without taking the cover off and looking at it. It's pretty easy to educate yourself if you don't know anything about alternators.

 

[bcngator00]

I wish I had the luck you guys are having getting the alternator out. I have tried going through the bottom and can't get the thing out and I have tried going through the top and can't get it by all the hoses and the tensioner pulley. I am leaning towards draining the radiator this weekend so I can completely remove the bottom radiator hose and try to get it out the bottom again and not crack/damage my fan shroud. That was my biggest obstacle going out the bottom. Oh, and the connector on the back of the alternator disintegrated when I pushed the tab down to pull it out of the alternator. So I will have to wire in a new connector.

One positive out of this hassle is that it appears that the alternator is the original as it still has the Toyota markings on it. 276K miles is pretty good out of one alternator. A testament to how Toyota builds vehicles. However, only 4K of those miles are under my ownership. I, too, have chosen a remanufactured Denso for the vehicle. We'll have to see how long it holds out. Hopefully it will have a decent life as I do not relish the idea of having to do this job again anytime soon. I had not thought about rebuilding the broken one on the vehicle now. That may be worth looking into for the next time . . .

 

[JunkCrzr89]

I haven't seen new bearings in denso rebuilds, nor regulator.
rectifier yes, brushes yes. I do wonder though, and assume now, that rebuilt densos don't automatically come with a list of new stuff.
I have two. My original was not the OEM stock unit at 180k.
What I did was redo the first one while I waited on the second to arrive. By the time it did my first one was redone and better than a rebuilt denso.
I thought that's weird, but at least there's a new rectifier on it and brushes. But old reg and old back bearing. Also old brush holder.
Oh well I guess.
My only concern about mine is the non oem regulator. BUT it's been great for at least 35k miles.

I wouldn't just install a new rebuilt denso without taking the cover off and looking at it. It's pretty easy to educate yourself if you don't know anything about alternators.

Interesting. I did the same as you - I bought a reman Denso but rebuilt my existing alternator while waiting for the reman to arrive. Once I got the reman in-hand I pulled the cover off and saw new brush holder with new brushes, as well as new regulator, but used/old resistor. The bearings felt as good as the new Toyota ones that I put in my existing unit, so I assumed the reman had new bearings; though I did not press apart to lay eyes on them. After reading Denso’s specs, it appears that they only replace the parts that don’t meet predefined thresholds during testing: Alternators.

 

[shevy77]

I wish I had the luck you guys are having getting the alternator out. I have tried going through the bottom and can't get the thing out and I have tried going through the top and can't get it by all the hoses and the tensioner pulley. I am leaning towards draining the radiator this weekend so I can completely remove the bottom radiator hose and try to get it out the bottom again and not crack/damage my fan shroud. That was my biggest obstacle going out the bottom. Oh, and the connector on the back of the alternator disintegrated when I pushed the tab down to pull it out of the alternator. So I will have to wire in a new connector.

One positive out of this hassle is that it appears that the alternator is the original as it still has the Toyota markings on it. 276K miles is pretty good out of one alternator. A testament to how Toyota builds vehicles. However, only 4K of those miles are under my ownership. I, too, have chosen a remanufactured Denso for the vehicle. We'll have to see how long it holds out. Hopefully it will have a decent life as I do not relish the idea of having to do this job again anytime soon. I had not thought about rebuilding the broken one on the vehicle now. That may be worth looking into for the next time . . .

I posted my detailed steps for removing out the bottom. See link, below. The biggest thing that I have found to help is removing the brackets which keep the hard lines together. It is two bolts to remove the hard line clamps. You will still have to slightly force through, but I never felt that I was about to damage anything.

RTH - alternator issues, Birmingham AL

hey guys. kinda reaching but might as well try and reach out to my fellow mudders. im currently far from home, in the middle of alabama. a few miles east of birmingham, pretty sure the tow truck is taking me to pell city or leeds. regardless, my destination is texas. all by myself and i’m pretty...

forum.ih8mud.com

 

[flintknapper]

I've done it both ways, top and bottom. Found it equally difficult, just for different reasons. Will probably pull it from the bottom next time it needs it.

It's a squeeze no matter which way you do it.

 

[94SRUNNER]

I've done it both ways, top and bottom. Found it equally difficult, just for different reasons. Will probably pull it from the bottom next time it needs it.

It's a squeeze no matter which way you do it.

A squeeze indeed!

 

[94SRUNNER]

Update -

My local alternator shop (Dayton Quality Starter) offers a complete tear down and rebuild, including new bearings, brushes, voltage regulator, and a rectifier for ~$120 with a 1yr warranty. I think I am going to drop my OEM unit there and install it when I do the radiator later this year. While I was there talking to them about my issues, they suggested getting the battery tested to eliminate that variable. I stopped by Advance Auto, where I sourced my battery last year, to have them test it and they said they battery despite only being a year old tested out of spec and replaced it under warranty with their new in house DieHard Gold brand. We shall see...

 

[gregnash]

Update -

My local alternator shop (Dayton Quality Starter) offers a complete tear down and rebuild, including new bearings, brushes, voltage regulator, and a rectifier for ~$120 with a 1yr warranty. I think I am going to drop my OEM unit there and install it when I do the radiator later this year. While I was there talking to them about my issues, they suggested getting the battery tested to eliminate that variable. I stopped by Advance Auto, where I sourced my battery last year, to have them test it and they said they battery despite only being a year old tested out of spec and replaced it under warranty with their new in house DieHard Gold brand. We shall see...

When you have the alternator our, why not look at having the shop rewind it for slightly higher output. Don't know what all you are running in your rig but could be worth it past the 100-130amps the stock unit puts out.

 

[94SRUNNER]

When you have the alternator our, why not look at having the shop rewind it for slightly higher output. Don't know what all you are running in your rig but could be worth it past the 100-130amps the stock unit puts out.

For my needs, I don't think that I need anything other than the factory 130 amp output. I run no accessories (beyond what was factory installed) other then chargers for phones/iPads on occasion.

 

[nckwltn]

I've pulled the alternator out of the top a couple of times now too. Unbolting the power steering pump and removing the air intake (not the air box) gives enough room to wiggle it out from the top.

I've not disconnected radiator lines, or power steering lines.

this is on an '03 LX with AHC

 

[94SRUNNER]

I've pulled the alternator out of the top a couple of times now too. Unbolting the power steering pump and removing the air intake (not the air box) gives enough room to wiggle it out from the top

After going through the process I can say it was unnecessary to unbolt the high pressure line on the power steering pump, I could have rotated the alternator and squeezed it out of the top. Oh well, I was able to add almost a quart of fresh fluid to the system, which doesn't hurt anything. Just added a few additional steps and mess to clean.

 

[JunkCrzr89]

I stopped by Advance Auto, where I sourced my battery last year, to have them test it and they said they battery despite only being a year old tested out of spec and replaced it under warranty with their new in house DieHard Gold brand.

Unsurprising to me if it was AA’s Autocraft brand battery... I’ve seen those die in 6 months...

 

[94SRUNNER]

Unsurprising to me if it was AA’s Autocraft brand battery... I’ve seen those die in 6 months...

I've had very good luck with them in the past and was surprised it didn't test to spec.

Prior to that I had an Interstate from Costco, which failed in about 4 months with a bad cell. My local Costco would not order the size battery I needed, so I just returned it and got a credit.