Where is the voltage regulator located? Overcharging alternator, trying to find the cause.

[98FordLove]

Does my explorer have a seperate standalone voltage regulator? Or is it inside the alternator itself?

My battery icon on my dash starting blinking on and off yesterday and the CEL came on. I didn't have a OBDII scanner on me (just ordered one now, lesson learned) so I couldn't pull the code. Stupid me I just assumed it was the same code again for faulty cats. So I kept driving. Turns out my alternator was overcharging and the truck is now at my mechanics shop and he just put in a rebuilt alternator and new battery tonight. Since I killed my battery last night right as I was near home and because it's -50C here, it kept constantly being drained without being completed charged up again. So the damage in the battery has been done. So it wasn't a failed alternator that caused my battery to die but an overcharging one, which I read can damage your battery and your wiring.

Another thing is, I drove the truck about an hour and a half with the CEL on. Do you think the overcharging alternator did damage to my electrical wiring? There's no doubt it caused damage to my battery and that's why I bought a new one today and it's charging inside my house right now first before installing it tomorrow.

 

[BrooklynBay]

The alternator has a regulator on the back. Did you check the voltage with a multimeter? Autozone could read the codes.

 

[98FordLove]

The alternator has a regulator on the back. Did you check the voltage with a multimeter? Autozone could read the codes.

Thanks. Yes my mechanic checked the voltage with a multimeter. But I don't know if he checked the voltage from the alternator or from the voltage regulator. I guess i should have asked him tonight if i should pick up a voltage regulator too. Not just replace the alternator but voltage regulator too.

After seeing this video, I thought the voltage regulator was inside the alternator.

 

[Fix4Dirt]

i thoguht mine was internal VR but might be wrong lets call @410Fortune

 

[cober]

probably worn brushes

 

[1.8TTony]

The regulator is screwed onto the back of the alternator. 4 screws. It's the piece where the wire harness connector plugs into.

Many times, when an alternator is over charging, this regulator is the problem.

In rare cases the alternator can over charge when the rectifier is the problem. The rectifier is the piece that the battery charge wire is bolted onto. The field terminal (lug).

The regulator also has the brushes on it. If the brushes are worn, simply replace the regulator. No need to replace the entire alternator.

 

[98FordLove]

The regulator is screwed onto the back of the alternator. 4 screws. It's the piece where the wire harness connector plugs into.

Many times, when an alternator is over charging, this regulator is the problem.

In rare cases the alternator can over charge when the rectifier is the problem. The rectifier is the piece that the battery charge wire is bolted onto. The field terminal (lug).

The regulator also has the brushes on it. If the brushes are worn, simply replace the regulator. No need to replace the entire alternator.

Thanks, good to know this. Will keep you posted. The mechanics shop is open in less than an hour from now, going to call him. He was certain the alternator is bad but not sure how he knew this.

 

[BrooklynBay]

Auto parts stores could bench test an alternator. There's no need to guess which part of it is bad.

 

[98FordLove]

I ju

The regulator is screwed onto the back of the alternator. 4 screws. It's the piece where the wire harness connector plugs into.

Many times, when an alternator is over charging, this regulator is the problem.

In rare cases the alternator can over charge when the rectifier is the problem. The rectifier is the piece that the battery charge wire is bolted onto. The field terminal (lug).

The regulator also has the brushes on it. If the brushes are worn, simply replace the regulator. No need to replace the entire alternator.

I just called my mechanic. He said the voltage regulator is inside the alternator. I mentioned that I thought it was on the outside of the alternator but he said it wasn't (didn't want him to think I'm questioning or doubting him). Maybe it's easy to easily miss not seeing it? How big is this regulator?

He said he put in the new alternator last night and the voltage readings now are normal.

Completely confused. If it's a voltage regulator going bad, then how are the voltage readings back to normal now by replacing the alternator?

But Im going to pick up the truck shortly and I will hook up a DMM to check the voltage too.

 

[BrooklynBay]

The regulator comes with the alternator. Mechanics like replacing parts as one assembly.

 

[C420sailor]

This is a terminology issue.

The “alternator” is the assembly that includes the alternator, regulator, etc etc. When people say “I changed my alternator” they mean they changed that whole unit.

Almost no shops will replace any parts internal to the alternator (regulator, etc). They just replace the whole thing as a unit, like your mechanic did.

It’s a totally reasonable and standard maintenance practice. And if your alternator was old, the rest of the components probably weren’t far from death anyway.

 

[donalds]

Maybe this picture will help

 

[donalds]

This may help these pictures

How to: - 4g alternator rebuild with pictures

So about a year ago I bought a remanufactured alternator From autocrap Since then the bearings went out twice making lots of noise So instead of changing it again for warranty I figured I may as well rebuild it the correct way and make a how to thread

www.explorerforum.com

 

[1.8TTony]

Yep, that's it..........and the later alternators don't have that sheet metal "cage" covering the back of the alternator.

 

[98FordLove]

The regulator comes with the alternator. Mechanics like replacing parts as one assembly.

Good to know this thanks.

This is a terminology issue.

The “alternator” is the assembly that includes the alternator, regulator, etc etc. When people say “I changed my alternator” they mean they changed that whole unit.

Almost no shops will replace any parts internal to the alternator (regulator, etc). They just replace the whole thing as a unit, like your mechanic did.

It’s a totally reasonable and standard maintenance practice. And if your alternator was old, the rest of the components probably weren’t far from death anyway.

That makes sense. I saw the regulator when my mechanic handed me the old one back. He made a mistake thinking the regulator was inside the alternator but it's actually outside of the alternator. I called a parts store and the regulator is only $20 to replace but with the rebuild alternator that I picked up it came with a new regulator on it.

So I could have just replaced the regulator as I don't know for sure if that alternator was actually bad or not. But the shop wouldn't know without taking it apart. Either way, preventative maintenance. The old alternator I believe was still stock so 26 years old.

I think the alternator has to come off anyways to replace the regulator? If so, then best to just put a rebuilt alternator on especially since my old one was still stock.

 

[98FordLove]

View attachment 437418
View attachment 437419
This may help these pictures

How to: - 4g alternator rebuild with pictures

So about a year ago I bought a remanufactured alternator From autocrap Since then the bearings went out twice making lots of noise So instead of changing it again for warranty I figured I may as well rebuild it the correct way and make a how to thread

www.explorerforum.com

Good to know this thanks. I don't know how the alternator sits when installed with the regulator on it. But is the regulator accessible to be replaced without having to remove the alternator or does the alternator have to come out to get to the regulator?

 

[Turdle]

If you can't fix it yourself, don't second guess the guy who can.

Cars fixed. No need for this trolling discussion.

 

[1.8TTony]

It’s a totally reasonable and standard maintenance practice. (Replacing the alternator as a whole unit).

I beg to differ. That statement might hold true for alternator designs of the 60's, 70's and 80's. But alternator components have come a long way.

Shops don't repair alternators because a shop makes a ton more money installing complete alternators rather than fixing them.

Think about it, how many times can you remove and replace an alternator on these Explorers?

Takes less than 10 minutes to replace them.

If a shop charges customers $150 hour labor and the shop employee changes 6 alternators in an hour, each one of those 6 customers are gonna pay the full $150 hour labor fee.

6 customers X $150 each labor fee = Shop earns $900 in 1 hour.

Versus, the 1 hour it takes the shop employee to rebuild a single alternator.

1 customer X $150 labor fee to rebuild the alternator = Shop earns $150 in that 1 hour.

One of my trucks is a 2004 F-150. It has 240,x.. miles on the odometer. The alternator is the original OEM unit which came with the truck when I bought the truck new back in 2003. I've replaced the $50 voltage regulator once and I've replaced a $10 rectifier. Total alternator maintenance cost over the past 18 years?.......$60. How much does an inferior replacement alternator cost? $400, and pay that much every 80,000 miles?

There was a time when it was infact cheaper to replace an alternator rather than rebuilding it because rebuilding was a very labor intensive process........that time has come and gone. The tables have turned and it's now cheaper to replace a single part in/on an alternator when it fails rather than rebuilding or completely replacing one.
.

 

[1.8TTony]

You can replace the voltage regulator without removing the alternator from the vehicle.......just be sure to disconnect one of the battery cables so that there's no chance of electrical sparks.......also, have a magnetic "grabber tool" handy incase you drop one of the regulator screws as you remove the regulator.

 

[98FordLove]

If you can't fix it yourself, don't second guess the guy who can.

Cars fixed. No need for this trolling discussion.

Not trolling or second guessing my mechanic. I'm glad the truck is fixed, but just curious if it was just the regulator that needed to be replaced. EIther way I have a newer alternator in vs a 26 year old one. Was probably risky driving with a 26 year old alternator (in any car).