Alternator Options

[ZiMMie]

The Valeo regulator fit. The Bosch one did not…I think it was a non-M part. It’s also ECS so it’s 50/50 whether anything fits

I was curious so i opened up my Bosch alternator to see what type of regulator was used.

To my surprise, it is actually a VALEO alternator refurbished by BOSCH.

It had a Valeo voltage regulator on there.
Ordered a replacement. For anyone that need a replacement Valeo Part number for the Voltage regulator is 593423.

[bigjae46]

I was curious so i opened up my Bosch alternator to see what type of regulator was used.

To my surprise, it is actually a VALEO alternator refurbished by BOSCH.

It had a Valeo voltage regulator on there.
Ordered a replacement. For anyone that need a replacement Valeo Part number for the Voltage regulator is 593423.

I think that's evidence that Bosch does NOT replace the regulator on a reman.

[OldRanger]

I think that's evidence that Bosch does NOT replace the regulator on a reman.

Probably not - I would just replace the brushes if I had the patience. They are cheap ($10-$20) and easy if you have the correct solder (probably some kind of high temp) and soldering iron to do the work.

I did not. So I bought new, but kept my failed alternator.

[bigjae46]

Probably not - I would just replace the brushes if I had the patience. They are cheap ($10-$20) and easy if you have the correct solder (probably some kind of high temp) and soldering iron to do the work.

I did not. So I bought new, but kept my failed alternator.

On another note, a Geniune BMW alternator has a limited lifetime warranty. It cannot have been fully covered by a BMW warranty. If a genuine BMW alternator was installed and paid for by a 3rd party warranty or insurance claim, it has the warranty. Just has to be paid for by someone other than BMW.

Very few dealership know about this...because they are dumb.

[jet_dogg]

Bosch also buys parts from part manufacturers and puts their name on them.

[OldRanger]

Update: AutohausAZ cancelled my online order "We regret to inform you that our stock for the following part number(s) has been depleted and no longer available"

So, I ordered one on Amazon via Newparts (Gordonsville, TN). https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Seems funny that FCP, Bimmerworld, and other online merchants don't have this alternator, but "Newparts" on Amazon does. I'll see what actually shows up on my doorstep.

[simon_c]

I went through 3 bosch alternators before I got a good one. Originally bought from FCP euro so they replaced for free but man I wish I knew this awhile back.

[bigjae46]

Bosch also buys parts from part manufacturers and puts their name on them.

Very possible but I've seen newish remans with obviously old or damaged brushes which are part of the regulator. So I very highly doubt that Bosch replaces the regulator. I'd at least remove and inspect the regulator before installing a reman alternator. It takes 5 minutes and will save you time, hassle, and a battery.

[Slideways]

Very possible but I've seen newish remans with obviously old or damaged brushes which are part of the regulator. So I very highly doubt that Bosch replaces the regulator. I'd at least remove and inspect the regulator before installing a reman alternator. It takes 5 minutes and will save you time, hassle, and a battery.

The regulator is not a low cost piece unlike the bearings. My guess is Bosch (or whoever they contract) cleans up the housing, replaces some of the low cost parts and bench tests the units. Unfortunately, when some of those alternators get installed, they don't pass a long term test, so they are a gamble.

Having replaced a higher mileage voltage regulator (one brush completely worn and not making contact) on another car, I would always start there when there is a voltage issue. The regulator is less than half the cost of the whole alternator.

As you said, if you get a refurbed unit, inspect the voltage regulator brushes. Rebuilding these alternators is not that hard and it is annoying that Bosch can't do a better job at refurbing them. Guess it is a cost thing. Other than the brushes and bearings, I don't know what else can wear out on these alternators.

[jet_dogg]

The regulator is not a low cost piece unlike the bearings. My guess is Bosch (or whoever they contract) cleans up the housing, replaces some of the low cost parts and bench tests the units. Unfortunately, when some of those alternators get installed, they don't pass a long term test, so they are a gamble.

Having replaced a higher mileage voltage regulator (one brush completely worn and not making contact) on another car, I would always start there when there is a voltage issue. The regulator is less than half the cost of the whole alternator.

As you said, if you get a refurbed unit, inspect the voltage regulator brushes. Rebuilding these alternators is not that hard and it is annoying that Bosch can't do a better job at refurbing them. Guess it is a cost thing. Other than the brushes and bearings, I don't know what else can wear out on these alternators.

In an effort to have a comprehensive catalog, Bosch will purchase parts from other suppliers and put their names on them.

Also brushes are paramount to service life. These are absolutely a wear item and should be replaced along with the vr, bearings less so since they provide audible indication of failure but still permit the alternator to function.

[Slideways]

In an effort to have a comprehensive catalog, Bosch will purchase parts from other suppliers and put their names on them.

Also brushes are paramount to service life. These are absolutely a wear item and should be replaced along with the vr, bearings less so since they provide audible indication of failure but still permit the alternator to function.

The brushes are part of the voltage regulator.

[jet_dogg]

The brushes are part of the voltage regulator.

I was under the impression the voltage regulator was an easy swap and someone had mentioned the brushes were soldered so I thought they were divorced from the regulator.

I also didn't bother to look at etk 😂

[OldRanger]

I was under the impression the voltage regulator was an easy swap and someone had mentioned the brushes were soldered so I thought they were divorced from the regulator.

I also didn't bother to look at etk 😂

To confirm: The brushes are in the regulator, soldered in via a wire lead, but very easy to get to. They can be replaced with a bit of a bother, for a fraction of the cost of a complete regulator. Since they wear out over time they are the most likely cause of a voltage problem on high mileage cars.

in retrospect, if you’ve still got an original alternator on an e46…and don’t want to risk loss of your vehicle for a few days or more when your alternator fails…just buy brushes and have a high temp soldering iron/solder. The repair is probably a 5 minute job once the alternator is on the bench.

[bigjae46]

A voltage regulator is less than $100. I’d rather do that than mess with soldering brushes on…and you should also replace the springs on the brushes.

[OldRanger]

For those of you that want to buy new, complete alternators, as of the time of this posting:

1. FCP Euro doesn’t have the Valeo, they lost it NLA. But they do have Genuine BMW reman for $550
2. Bimmerworld carries the Valeo in their catalog but doesn’t indicate “In Stock”
3. ECS Tuning has the Valeo in stock for $395
4. Amazon merchants, AutoZone, etc. have the Valeo 439317 for about $290. It’s a new one, no core charge.