Replacing alternator brushes / regulator on car

dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
First off let me apologize for not taking pictures.

My goal here is to save people like me about 30 minutes when changing alternator brushes without removing the alternator from the car. The below is very obvious once you have already removed he brushes, but prior it is a bit of a mystery.

This procedure can all be done from the top without jacking the car up ore removing the skid plate assuming you don't drop any tools/ fasteners. Even if you do chances are you will be able to reach them from the top.

Back of alternator to me is drivers side (hold over from longitudinal engine mounting).

To remove brushes.
0) disconnect battery, don't argue on this one, your wrench will have + 13 volts 150 amps (fuse size) on many occasions.
1)Remove any aftermarket oil pressure sensors that get in the way of the plugs on back side of alternator (ask me how I know).
2) remove heavy Alternator wire with 13mm ratchet and the 2 pin connector both from back of alternator using your fingers and maybe a bit of help from a flathead screwdriver.
2) remove alternator wire (harness to battery) holder at bottom of alternator using 8 mm, I used the deep 1/4" drive on a small ratchet. The steel bracket has to be wiggled quite a bit to get it off of the stud.
3) remove secret #2 Phillips bolt at bottom of alternator (previously coverd by wire holder) holding black back cover over the regulator/ alternator.
4) remove the 13mm nut below the first 13mm nut that you removed to get the heavy wire off. Here is where I poked for a good 15 minutes after hearing that you don't have to remove this, you do.
5) The cover should wiggle off at this point. If it doesn't, figure out why.
6) remove 15mm nut toward the pulley (same stud) of the 13mm nut you already removed (same orientation).
7) remove 3 #2 Phillips bolts holding regulator to alternator (2 mounts, 1 terminal).
8) remove brush/ regulator assembly by sliding up.
9) re-install in reverse, note that the new brushes are somewhat delicate and must be compressed on to the communicator.

Enjoy your new found voltage.

I purchased a genuine Bosch regulator from an eBay seller named American Engines (I know, weird). Was about $70 and arrived well packaged in 3 days.

Below is Edit
One I purchased (I know link will die) http://www.ebay.com/itm/160848443559#ht_1807wt_1180 Part Number F-00M-145-200, OR F-00M-145-209

Copy / paste from Auction

GUARANTEED to fit:


VOLKSWAGEN




LT 2.5L TDI, SDI 1998-ON

TRANSPORTER 2.5 TDI 1998-ON

TRANSPORTER 3.2L 2003-ON

CALIFORNIA 2.5L TDI 2001-2003

CARAVELLE 2.5L TDI 2001-2003
MULTIVAN 2.5L TDI 2001-2003

Dimensions

12 Volt
14.5 Volt set
A-Circuit
L and DFM
Internal Fan Units

Interchanges with the following original numbers

BOSCH F-00M-145-200, F-00M-145-209, F-00M-145-225, F-00M-145-350
MERCEDES BENZ 003-154-24-06, 003-154-53-06
PORSCHE 000-043-206-37
VOLKSWAGEN 038-903-803, 038-903-803B, 038-903-803E, 038-903-803EX

Alternator Numbers

BOSCH 0-124-215-006, 0-124-315-030, 0-124-325-057, 0-124-325-074, 0-124-325-075, 0-124-325-125, 0-124-515-001, 0-124-515-013, 0-124-515-015, 0-124-515-038, 0-124-515-039, 0-124-515-042, 0-124-515-062, 0-124-515-073, 0-124-515-083, 0-124-615-006, 0-124-615-014, 0-124-615-016, 0-124-615-026 VALEO TECH 572906
VOLKSWAGEN 021-903-025T, 021-903-026, 021-903-026B, 028-903-031, 036-903-024E, 037-903-026B, 037-903-026C, 074-903-025J, 074-903-025S
 
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BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Great Write-up. I was unsure that we could change out the regulator like the older ones
 

gallaj01

Veteran Member
Joined
Mar 25, 2008
Location
Madison, WI
TDI
2002 Jetta Wagon TDI GLS, 2001 Jetta TDI GLS, 2017 Golf AllTrack
I too was not sure if the regulator could be replaced on these alternators. Good to know!.

I was tracing an alternator problem myself and found that i needed to make a new grounding strap and clean all ground points on car. The grounding point under the battery tray was complete crap.
 

dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
A good buddy of mine informed me that this was possible, Big thanks Deebeaux
DriveBiWire is a strong proponent of replacing the regulator.
After doing the install it is obvious that Bosch intended it to be serviced, only wear parts remaining are bearings and pulley.
I did grab 1 pic and will be doing a few illustrations in a week or so.
 

Genesis

Top Post Dawg
Joined
Feb 26, 2003
Location
Sevier County TN
TDI
'03 Jetta Wagon
Yes, but be aware that the slip rings may be worn and if they are your new brushes will wear out very fast.

You can't inspect them very well (if it all) doing this on the car.....
 

dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
You have visual on 180 degrees of the slip rings, then rotate motor by hand to see the rest if so desired.

The only reason I could imagine that the new brushes would wear faster than the old would be if contaminates got in. You can also sand them smooth if desired. Not as good as putting it on a lathe, but should work fine.
 

TDIUS

New member
Joined
Oct 13, 2010
Location
Cincinnati, OH
TDI
2002 Jetta ALH engine automatic
How can we replace just the brushes in the voltage regulator?
I have seen 18x8x5 mm carbon brushes for Bosch VRs on several sites for about $5/pair.
The VR itself is still fine; it's just that the carbon brushes are worn down.
Several sites show how to replace brushes on other Bosch VRs, but they look different from this one.
Part no BR14-MO F 00M 145 225 3RO
The cap right here \ at the top appears glued on, the brush springs/

mountings are under the cap. Anyone know where to get the brush replacements for this VR?
 

dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
How can we replace just the brushes in the voltage regulator?
I don't know if that would be reliable/ possable, the plastic housing for the brushes are sonic welded, so I'd expect it to break when you open them up.
 

PDJetta

Top Post Dawg
Joined
Nov 6, 2003
Location
Northern Virginia
TDI
'04 Jetta GLS TDI Pumpe Duce Platinum Grey w/ Leather
I'd like to know this too. I've replaced the brushes on the A1 and A2 VW voltage regulators, but you could get at them and their lead solder points on the regulator. It appears the A4 VRs are hermetically sealed.

--Nate
 

Ski in NC

Top Post Dawg
Joined
Jul 7, 2008
Location
Wilmington, NC USA
TDI
2001 Jetta ALH 5sp stock
I'm with Genesis. If brushes wear down to the nubs, slip rings are probably rough. New brushes will eat up fast afterwards. If reg alone failed, and brushes ok, then new brushes should last. When brushes wear to the end, at the very end they arc, and that roughens the slip rings.
 

turbocharged798

Veteran Member
Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
You can buy new slip rings off ebay for a few bucks. Problem is that requires complete disassembly of the alternator to replace it. Might as well replace the bearings while you are in there well.

Oh, there is no way to replace brushes on the sealed VRs. I tried, they are completely sealed.
 

legoleg

Well-known member
Joined
Mar 28, 2002
Location
Flint, MI
TDI
2002 Jetta
Thanks for the post, this along with some others saved me $850 over having the dealership replace the alternator (though I would have never paid it). I would just add to the instructions above that a short 13mm socket won't be enough, you'll need a deeper one too. Also, a screwdriver with a bendable shaft will help immensely. Here is where I got my voltage regulator, a Bosch for $53:
http://www.autopartswarehouse.com/s...55.html?intcmpid=Product+Listings+Best+Seller
 

veget8

Veteran Member
Joined
Aug 9, 2002
Location
Randolph, VT
TDI
Golf, 2002, Silver
I just did this on my 02 Golf. First off, thanks a lot to Dremd for posting that great info. It did save me a lot of time. I have a few pointers to add that worked for me. I ended up removing the A/C compressor. My reasoning for this is that I found it was just too tight for me to get to all the little screws and nuts from the topside only. Maybe it was my particular car, maybe it was my hands, I don't know. Anyway, if you're interested in an alternative that is slightly more involved, but gives you more room, here's the basic overview:
  • Jack up the vehicle and place on jackstands
  • Disconnect battery
  • Disconnect oil pressure sensor connector (optional, gives you a tiny bit more room to get your hand in)
  • Remove passenger side wheel
  • Remove belly pan and passenger side skirt
  • Disconnect alternator light connector and A/C clutch connector
  • Release the tensioner and move the belt off the A/C compressor pulley
  • Remove the two A/C compressor bolts (16mm)
  • Remove the A/C compressor
Now you can follow the remainder of the Dremd procedure from below or on top, whatever is better for the screw or nut you are tackling, and even have a fair amount of room to get your hand in there. I did not notice a 13mm nut on the same stud as the 15mm nut, it was on its own stud (toward the firewall).
Tool-wise, I have a few recommendations that helped me as well:
For the tensioner, I use a 16mm box end/spanner wrench (which I then grab with another box end wrench over the spanner end of the first). The two wrenches together give you beau coup leverage, and make it way easier and safer.
The phillips screws were the hardest to get off. The following came in handy:
  • a right angle screw driver
  • a phillips screw gun bit, electrical-taped inside of a 1/4" socket for a tiny screw driver
  • a stubby phillips screw driver
To get the A/C compressor back on, I used a 4 pound dead blow and a mirror, in leau of the spreading procedure that Dremd outlined.
One more thing, I replaced my regulator with a knock-off one from DS Auto LTD on eBay, for $22 with free shipping (brand new). Feel free to think of it as brave or foolish, but it was less than half the price, and it wasn't dead on arrival. Also, anyway you look at it, my previous OE Bosch regulator did fail. My slip rings are perfect and the brushes were at 10mm, 5mm over the wear limit. I'll be sure to report any issues I have with the new one.
 

dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
Glad to be useful.

Best of luck on $22 regulator. There is not much reason it couldnt be made for that price point, andI'd bet that the rebuilders use something at this price point, or lower. I thought about getting a cheaper one, but at the time, it was this, or a $200+ alternator, so I looked at this as the cheap(er) way.

FYI: for others, A/C removal would certainly add some space, but you should definitely be able to do it all from top without even jacking the car up (except when you drop tools on the skid plate).
 

Lars Haeh

New member
Joined
Jun 1, 2013
Location
Toronto, ON, Canada
TDI
Golf MK4
I found out that even though the plastic around the brushes is ultrasonically welded in, they are still very easy to remove, at least from my Valeo alternator:
All you have to do is get a hold of the brush with pliers, then pull on it while holding a very high wattage soldering iron (I used a torch attachment) to the other end. It is actually the braided copper lead from the brush that holds it in, desoldering it lets you just pull it out. The high wattage soldering iron is needed as the copper leads rapidly conduct the heat away. For mine, new brushes are $7, brushes and slip ring are $13, and a kit with those and the bearings is $30.
 
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dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
I found out that even though the plastic around the brushes is ultrasonically welded in, they are still very easy to remove at least from my Valeo alternator:

All you have to do is get a hold of the brush with pliers, then pull on it while holding a very high wattage soldering iron (I used a torch attachment) to the other end. It is actually the braided copper lead from the brush that holds it in, desoldering it lets you just pull it out. The high wattage soldering iron is needed as the copper leads rapidly conduct the heat away. For mine, new brushes are $7, brushes and slip ring are $13, and a kit with those and the bearings is $30.

Major win!
Excellant info
Thanks!
You may want to scale that pic down a bit.
Also, where did you get the brushes/ slip ring/ bearing?
 

Lars Haeh

New member
Joined
Jun 1, 2013
Location
Toronto, ON, Canada
TDI
Golf MK4
Major win!
Excellant info
Thanks!
You may want to scale that pic down a bit.
Also, where did you get the brushes/ slip ring/ bearing?
I found all that stuff on ebay, prices include international shipping.

Sorry about the big image, the BB-code resize option didn't work when I tried it. I replaced it with a smaller one.
 

Sunday_Kim

Member
Joined
Aug 25, 2002
Location
Canada
TDI
2002
Great post so far. Many thanks to the poster and i saved $1,000. I'm a relative noob so i am adding a few additions to the instructions to help other noobs...maybe the administrators could move this higher up since i think it will help.

On my 2002 Canadian TDI, my setup is slightly different.
1) Test to make sure it is the alternator. There's lots of posts on this...take battery in for load test, check for corrosion on terminals, use voltmeter to check for 14v. Assuming it is the alternator/ voltage regulator/ brush, proceed.
2) The wiring plug top clip needs a screwdriver but the force seems to be straight out perpendicular from voltage regulator. If you look at the new replacement part, you will see the small tab that holds it in. I think the long screw driver is supposed to lift it above the tab but be careful because the plastic where the screw driver slides in may be brittle.
3a) There is a round black plastic cap on top of the nut (13mm) on the main connection to the battery. The cap just slips off with no thread. I used a screw driver to start and then your fingers to pull it off.
3b) Once you remove the wire, there is another 13mm nut underneath. It also needs to be removed.
4) The 8mm nut can be found by following the wiring. It can barely be seen from the top but definitely found by feeling with your finger. It may be seized so be careful you don't round off the 8mm nut. (If you round it, you can try a 5/16" nut since it is slightly smaller than 8mm or buy a damaged nut socket that will bite into the nut as you remove it.) A little penetrating oil might help to start. If you can't get it off, you might have to pull the alternator out. (It only holds a metal "L" to hold the wiring harness in place. I did not re-install the metal bracket and nut and chose to use nylon ties to keep the wire in place.)
5) My alternator has a plastic bracket - not steel - and is held on by additional fasteners. Removing the undershield will give you a clear view from underneath. Inside one of the holes under the 8mm nut you removed is a phillips head screw that you have to remove. It's deep enough in the hole, you can't see it from above.
6) Underneath the wiring plug is another 13mm nut with a funny washer on it. It's where the copper crescent moon on the new voltage regulator slides it. Although you can remove the plastic bracket without removing this nut, it should be removed to reduce the possibility of cracking the plastic. (I widened the hole so the washer can pass through freely when i put it back together.
7) The rest went as the original post. Many thanks.


!!! I don't think i can add pictures with my profile but found this site useful for picture on the Bosch alternator...http://mbworld.org/forums/w211-amg/...placement-diy-its-usually-not-alternator.html


Question (now answered...rounded nut):
So now i am onto the nut that holds the steel bracket. This post says 8mm but it seems to slip off. I've tried 7mm (too small), 1/4" (too small), 9/16" (slips off) and they don't work. Is it possible that this is a 7.5mm bolt. I've seen that there is a 7.5mm hex tool for VW shocks so i'm wondering if this is 7.5mm.

If it truly is 8mm, any suggestions before i take a damaged bolt remover socket (teeth will destroy the socket)? Gator socket seems too big to fit around the wire harness but i'm wondering if there are any other tools that would be good to try around such little room to work?
 
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dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
I don't own a 7.5 mm outside wrench, so on MY car was almost certainly a 8mm (it could have been 7mm).
Yours could be different.
 

Dennis1979

Well-known member
Joined
Apr 12, 2008
Location
Netherlands
TDI
VW Golf IV '02, 1.9 ASV
Tried yesterday to replace the regulator and brushes. The nut who holds the bracket is a 8mm socket.

I did not succeed, before i started i bought the wrong replacement, I need a part number 225 on the end, and had bought a wrong number 300 (difference is a A / B circuit type) so I have to buy another regulator today.
 

isonic

Veteran Member
Joined
Aug 11, 2009
Location
St. Paul, MN
TDI
2003 Golf 4door 5spd
First off let me apologize for not taking pictures.

To remove brushes.
0) disconnect battery, don't argue on this one, your wrench will have + 13 volts 150 amps (fuse size) on many occasions.

1)Remove any aftermarket oil pressure sensors that get in the way of the plugs on back side of alternator (ask me how I know).

2) remove heavy Alternator wire with 13mm ratchet and the 2 pin connector both from back of alternator using your fingers and maybe a bit of help from a flathead screwdriver.


2) remove alternator wire (harness to battery) holder at bottom of alternator using 8 mm, I used the deep 1/4" drive on a small ratchet. The steel bracket has to be wiggled quite a bit to get it off of the stud.


3) Remove secret #2 Phillips bolt at bottom of alternator (previously coverd by wire holder) holding black back cover over the regulator/ alternator.

4) remove the 13mm nut below the first 13mm nut that you removed to get the heavy wire off. Here is where I poked for a good 15 minutes after hearing that you don't have to remove this, you do.

5) The cover should wiggle off at this point. If it doesn't, figure out why.

6) remove 15mm nut toward the pulley (same stud) of the 13mm nut you already removed (same orientation).

7) remove 3 #2 Phillips bolts holding regulator to alternator (2 mounts, 1 terminal).

8) remove brush/ regulator assembly by sliding up.


9) re-install in reverse, note that the new brushes are somewhat delicate and must be compressed on to the communicator.

Enjoy your new found voltage.

I purchased a genuine Bosch regulator from an eBay seller named American Engines (I know, weird). Was about $70 and arrived well packaged in 3 days.

Below is Edit
One I purchased (I know link will die) http://www.ebay.com/itm/160848443559#ht_1807wt_1180 Part Number F-00M-145-200, OR F-00M-145-209

Copy / paste from Auction

GUARANTEED to fit:


VOLKSWAGEN




LT 2.5L TDI, SDI 1998-ON

TRANSPORTER 2.5 TDI 1998-ON

TRANSPORTER 3.2L 2003-ON

CALIFORNIA 2.5L TDI 2001-2003

CARAVELLE 2.5L TDI 2001-2003
MULTIVAN 2.5L TDI 2001-2003

Dimensions

12 Volt
14.5 Volt set
A-Circuit
L and DFM
Internal Fan Units

Interchanges with the following original numbers

BOSCH F-00M-145-200, F-00M-145-209, F-00M-145-225, F-00M-145-350
MERCEDES BENZ 003-154-24-06, 003-154-53-06
PORSCHE 000-043-206-37
VOLKSWAGEN 038-903-803, 038-903-803B, 038-903-803E, 038-903-803EX

Alternator Numbers

BOSCH 0-124-215-006, 0-124-315-030, 0-124-325-057, 0-124-325-074, 0-124-325-075, 0-124-325-125, 0-124-515-001, 0-124-515-013, 0-124-515-015, 0-124-515-038, 0-124-515-039, 0-124-515-042, 0-124-515-062, 0-124-515-073, 0-124-515-083, 0-124-615-006, 0-124-615-014, 0-124-615-016, 0-124-615-026 VALEO TECH 572906
VOLKSWAGEN 021-903-025T, 021-903-026, 021-903-026B, 028-903-031, 036-903-024E, 037-903-026B, 037-903-026C, 074-903-025J, 074-903-025S
I added pictures to the original post to help out others. Couple of notes, I have a 2003 Golf with the Bosch 120 A alternator. I used the F-00M-145-200 part number. If you google search this part number you will find ebay sellers. I got mine from justautopartsinc. Great seller, $30 with free shipping.

A few things, I had to remove the 15MM nut before I could get the black plastic cover off the back of the alternator.

Pay attention to which holes the three screws come out of in step 7, they are not all the same length.

All my pictures are from the bottom/ underneath the car. I ended up getting the car in the air and removing my skid plate after I dropped my first tool :). In the end I think it is worth the time to do this if you are doing this for the first time.

This isn't a hard job, just a little tedious. Nothing to be afraid of though. You should be able to do this for the first time in 2 hours.

My symptoms of a failing regulator were:

1. Battery light started flickering on intermittently.
2. Battery light became more steady.
3. With a voltmeter I measured no charging voltage after I started the car. I.e. after starting the car and letting the motor idle I still read 12.5V. Only after increasing engine RPM did I finally get 14.5V.

All of these symptoms were intermittent for me and were diagnosed over a long period of time. I drove the car for a while trying to figure out the issue.
 
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dremd

Veteran Member
Joined
May 31, 2007
Location
South Louisiana
TDI
06 sprinter. 03 jetta wagon premium with 6 speed ALH swap, 14 JSW
Very highly appreciated upgrade.
Thank you.
 

cgi2099

Veteran Member
Joined
Aug 23, 2010
Location
Oklahoma
TDI
Jetta 1999.5
Installed new brushes/regulator, worked for a day, now getting zero voltage again. Replaced old regulator with identical new bosch part# F-00M-145-225? Any ideas, is there something that can go wrong inside the alternator to make the regulators go bad?
 

freedomlives

Veteran Member
Joined
Aug 8, 2011
Location
Slovakia
TDI
2005 VW Transporter T5, 1999 Skoda Octavia I 1.9TDI
Installed new brushes/regulator, worked for a day, now getting zero voltage again. Replaced old regulator with identical new bosch part# F-00M-145-225? Any ideas, is there something that can go wrong inside the alternator to make the regulators go bad?
I just installed a new regulator (this is a great write up!). One thing that I noticed on re-installation was that loop of wire that needs to be screwed down onto the regulator. I'm not 100% sure that it was screwed under the regulator I removed, which I think was installed a couple of years ago when a shop rebuilt the alternator.

Unfortunately, one of the old screws was totally stripped, and I ended up dremelling away a chunk of the old regulator to get pliers around the offending screw. So I can't check if the old regulator was actually bad...

But I think it is possible that that loop of wire on mine wasn't screwed down, but just ended up being pressed against the screw by the plastic cover, and after several years vibrations, heat-cold, whatever moved it.

I could be totally wrong, but you did screw back down the loop of wire under the screw terminal shown in step 7?
 

hooville

Veteran Member
Joined
Jan 13, 2003
Location
Marietta, GA
TDI
2000 Golf GLS, 2016 GTI, 2015 TDI Sportwagen S
Many thanks to all who wrote and updated this DIY, I am back on the road again with no battery light! 2003 ALH wagon, 120A Bosch alternator. My original regulator was Bosch F 00M 145 261 and I replaced it with a Bosch F 00M 144 136 from RM European Auto Parts ($30 IIRC). There seem to be a lot of different regulators that work on these alternators since the interchange lists seem to be quite extensive! Took me a little over 1.5 hours, all top side. An inspection mirror and a magnetic retrieval tool were very helpful!
 
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