Adjustable Voltage Regulators
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Adjustable Voltage Regulators
for your Volvo/Bosch Alternator

   CLICK HERE FOR INSTALLATION TIPS

Customer Comments:
"I finally have appropriate alternator output voltage.  My car has never had enough voltage from its charging system.  I installed your regulator, and was thrilled by the results.  My Autronic SM2 engine management system is much happier.  It idles noticeably better now, and I expect longer battery life as well.   Thank you for an excellent product.  Thank you for your fast service."   R.L., 1984 BMW 633 CSi/Dinan turbo/SM2

"Installed both regulators.  First thing I noticed was that both cockpit voltmeters were off by about a volt or more.  Knowing the voltage at the battery terminals is a great relief.  Both regulators tuned to 14.5 volts and seem to working GREAT.  Thanks for making these fabulous products available."  '79 BMW R100RS motorcycle and '84 BMW 663CSi,  J.M., Jacksonville, FL.


ALL IN STOCK
 


NEW External Adjustable Regulator Kit: In Stock
This kit incorporates a separate brush assembly that will replace your existing Bosch internal voltage regulator assembly in the rear of your alternator, plus a remote regulator that can be mounted on a fender, etc. (further away from energy-robbing engine heat).  This regulator is adjustable to 15 volts and includes a 32 inch wire harness with plugs.  The harness is covered with high quality black poly-vinyl, that matches the original harness covering in your Volvo (not the cheap corrugated split-loom stuff you would normally see with such a kit).  The voltage adjustment is done with a small screwdriver on the under side of the regulator; clockwise to increase voltage; counter-clockwise to decrease voltageThese are new parts, not remanufactured.

******Also, if a 32 inch harness is not long enough for your installation, I can supply a custom length harness of any length for an additional $10.00.   You can choose a finished length or you may request it with one end unassembled (you can trim to desired length and assemble the connector end).

This style regulator works very well with the Volvo 240/260 series cars (especially 240 Turbos) since the alternator is very low in the engine bay and access to the back of the alternator for adjustments can be difficult (impossible in a 240 Turbo).  Also on a 240 the hot exhaust manifold is close to the alternator and by putting the remote regulator a distance away from this heat source, it will operate more consistently.  This is just one reason why having a remote adjustable regulator mounted somewhere more convenient is such a nice idea.  Scroll down to the installation tips to see how I installed this kit in one of my own 240's.
(Please read WARNING below regarding installation)

Will fit all Volvo 240/260 '75-'93, 740/760 '84-'92, 940/960 '91-'95.
I have found that these regulators will also fit other Bosch external fan alternators.  This particular type fits those with 28mm slip rings (A 32mm slip ring type is also available in an Internal Regulator type only... please inquire).  Most Volvos use 28mm slip rings. There are 28mm slip ring types found in many Saabs, VW's, Audis and others too.  Scroll down for Part Number Cross-References if you are not sure.

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Ordering: External Adjustable Regulator Kit
(select Standard Harness or Custom Length)

Price: $44.00 plus shipping
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20% discount
applies on orders of TWO or more (i.e.: two for $35.20 each plus shipping)
Your discount will be computed upon check-out.

Need a Replacement Brush Assembly?
Price: $12.00 plus shipping
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Shipping for External Regulator Kit
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         Shipping to CANADA:
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International Shipping (all other countries):  International Priority Mail insured: $24.00 (5 to 10 days)



 
NEW External Voltage Regulator (regulator only): This adjustable external regulator is the same one included in the above kit, but is available separately.  For those of you with 1980 and older Volvos that came originally equipped with a remote external regulator type setup, this is a direct plug-in item.  This is a new part, not remanufactured.  

This regulator corresponds to the following Volvo Part Numbers:

214 719

1 234 519

1 308 030

241 534

241 808

241 960

246 585

530165

530 878

531 914

588 950

 


This regulator corresponds to the following Bosch Part Numbers:

0 190 062 001

0 190 062 002

0 190 062 004

0 190 062 005

0 190 062 007

0 190 600 001

0 190 600 004

0 190 600 005

0 190 600 006

0 190 600 008

0 190 600 009

0 190 600 010

0 190 600 011

0 190 600 012

0 190 600 013

0 190 600 014

0 190 600 016

0 190 600 018

0 190 600 020

0 190 600 021

0 190 601 001

0 190 601 002

0 190 601 003

0 190 601 006

0 190 601 007

0 190 601 008

0 190 601 009

0 190 601 010

0 190 601 011

0 190 601 012

0 190 601 013

0 190 601 017

0 192 062 001

0 192 062 004

0 192 062 005

0 192 062 007

9 190 085 001

9 190 087 011

 

 


(Please read WARNING below regarding installation)

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Ordering: External Adjustable Regulator Only (no harness or brush assembly) In Stock
Price: $32.00 plus shipping
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applies on orders of TWO or more (i.e.: two for $25.60 each plus shipping)
Your discount will be computed upon check-out.

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         Shipping to CANADA:
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Shipping cost is the same for one or multiple items.
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*************************************************************************


NEW Internal Adjustable Voltage Regulator:  In Stock
This complete regulator/brush assembly can be installed in your alternator in place of your original Bosch non-adjustable one.  It's an all-in-one compact part and can be adjusted to 15 volts.  This style works well in the Volvo 740/760 or 940/960 series cars where the alternator is mounted high (on top) and the back of the alternator is more easily accessible when an adjustment is needed. Adjustment is done with a small screwdriver in the hole you see in the back of the regulator; clockwise to increase voltage; counter-clockwise to decrease voltage.  This regulator will work in a 240 also, but access to the adjustment screw might be obstructed as mentioned above.  
This is a new part, not remanufactured.  (Please read WARNING below regarding installation)

Will fit all Volvo 240/260 '75-'93, 740/760 '84-'92, 940/960 '91-'95.
I have found that these regulators will also fit other Bosch external fan alternators.  This particular type fits those with 28mm slip rings (A 32mm slip ring type is also available in an Internal Regulator type only).  Most Volvos use 28mm slip rings. There are 28mm slip ring types found in many Saabs, VW's, Audis and others too.  Scroll down for Part Number Cross-References if you are not sure.

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Ordering: Internal Adjustable Regulator (May 26, 2008: Temporarily out of stock.  Should only be a few days)
Price: $32.00 plus shipping
Order Quantity:
After clicking "Add to Cart" above, please select your preferred Shipping below.

20% discount
applies on orders of TWO or more (i.e.: two for $25.60 each plus shipping)
Your discount will be computed upon check-out.

Shipping for Internal Regulator
Please Select Shipping for this Item and click "Add to Cart"
                            USA Shipping:
         Shipping to CANADA:
Other International Shipping:  
                                          
To View Cart or Check Out please click below:
Shipping cost is the same for one or multiple items.
U.S. shipping: $6.00 for Priority Mail insured.
Canada shipping: International Priority Mail (insured): $17.00 (estimated delivery in 5 to 10 days)
International Shipping (all other countries):  International Priority Mail insured: $24.00 (5 to 10 days)

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: $6.00 for Priority Mail insured.

Canada shipping: Priority Mail International insured: $16.00 USD (estimated delivery: 3 to 5 days),
All Other International Shipping:  Priority Mail International insured: $20.00 (5 to 10 days)

20% discount on orders of two or more pieces.

Bosch Alternator -- External Fan with 28mm Slip Ring
A 28mm External or Internal Adjustable Regulator will exchange correctly with these Voltage Regulator Part Numbers
Alfa-Romeo 116100506011, 119130506000, 119130506023, 705684800000
Audi/VW 034 903 803, 068 903 803,  068 903 803D
BMW 1711391, 1231-1726002, 1231-1279548, 1232-1711399, 1232-1271644,  1231-1271664
Bosch 0-120-468-001, 0-120-468-002, 0-120-468-003, 0-120-468-006, 0-120-468-070; 0-120-469-002, 0-120-469-003, 0-120-469-012, 0-120-469-015, 0-120-469-541, 0-120-469-542, 0-120-469-545, 0-120-469-546, 0-120-469-551, 0-120-469-552, 0-120-469-553, 0-120-469-554, 0-120-469-556, 0-120-469-558, 0-120-469-559, 0-120-469-560, 0-120-469-561, 0-120-469-566, 0-120-469-575, 0-120-469-576, 0-120-469-577, 0-120-469-578, 0-120-469-581, 0-120-469-582, 0-120-469-586, 0-120-469-587, 0-120-469-593, 0-120-469-594, 0-120-469-595, 0-120-469-598, 0-120-469-599, 0-120-469-600, 0-120-469-602, 0-120-469-603, 0-120-469-604, 0-120-469-605, 0-120-469-606, 0-120-469-607, 0-120-469-610, 0-120-469-617, 0-120-469-618, 0-120-469-619, 0-120-469-621, 0-120-469-622, 0-120-469-623, 0-120-469-624, 0-120-469-631, 0-120-469-632, 0-120-469-633, 0-120-469-635, 0-120-469-636, 0-120-469-637, 0-120-469-638, 0-120-469-639, 0-120-469-640, 0-120-469-648, 0-120-469-649, 0-120-469-650, 0-120-469-651, 0-120-469-654, 0-120-469-666, 0-120-469-674, 0-120-469-675, 0-120-469-677, 0-120-469-689, 0-120-469-690, 0-120-469-696, 0-120-469-697, 0-120-469-698, 0-120-469-699, 0-120-469-700, 0-120-469-701, 0-120-469-702, 0-120-469-703, 0-120-469-704, 0-120-469-705, 0-120-469-706, 0-120-469-707, 0-120-469-708, 0-120-469-710, 0-120-469-711, 0-120-469-712, 0-120-469-714, 0-120-469-715, 0-120-469-716, 0-120-469-717, 0-120-469-718, 0-120-469-719, 0-120-469-720, 0-120-469-721, 0-120-469-727, 0-120-469-728, 0-120-469-729, 0-120-469-732, 0-120-469-733, 0-120-469-734, 0-120-469-735, 0-120-469-737, 0-120-469-739, 0-120-469-740, 0-120-469-741, 0-120-469-742, 0-120-469-743, 0-120-469-754, 0-120-469-757, 0-120-469-758, 0-120-469-759, 0-120-469-768, 0-120-469-775, 0-120-469-776, 0-120-469-778, 0-120-469-780, 0-120-469-782, 0-120-469-783, 0-120-469-790, 0-120-469-794, 0-120-469-795, 0-120-469-804, 0-120-469-805, 0-120-469-806, 0-120-469-816, 0-120-469-817, 0-120-469-818, 0-120-469-819, 0-120-469-820, 0-120-469-821, 0-120-469-822, 0-120-469-823, 0-120-469-828, 0-120-469-830, -831, -832, -834, -835, -836, -839, -845, -846, -862, -863, -864, -865, -868, -869, -876, -877, -878, -879, -885, -886, -887, -888, -901, -902, -903, -904, -906, -907, -908, -918, -919, -967, -971, -972, -975, -998; 0-120-484-012; 0-120-488-114, -152, -183, -184, -219, -220, -221, -238, -245, -246, -247, -249, -254, -263, -264, -265, -279, -280, -976; 0-120-489-002, -003, -004, -005, -006, -007, -008, -009, -010, -011, -012, -013, -014, -015, -016, -017, -028, -029, -030, -031, -036, -037, -038, -039, -040, -041, -042, -043, -044, -045, -046, -057, -058, -062, -063, -076, -077, -080, -081, -082, -083, -093, -094, -107, -108, -109, -110, -111, -112, -113, -114, -115, -116, -117, -120, -121, -122, -128, -129, -130, -131, -133, -134, -137, -138, -139, -141, -142, -143, -144, -152, -153, -154, -167, -170, -171, -186, -191, -195, -196, -197, -198, -199, -200, -201, -202, -203, -204, -205, -206, -207, -208, -209, -210, -211, -215, -217, -218, -220, -228, -229, -235, -236, -237, -238, -239, -246, -247, -248, -249, -250, -260, -261, -262, -282, -283, -308, -338, -349, -351, -352, -353, -365, -366, -367, -368, -369, -370, -371, -372, -373, -380, -381, -385, -386, -401, -403, -418, -419, -420, -421, -422, -423, -432, -433, -434, -436, -437, -438, -474, -486, -487, -489, -493, -494, -549, -903, -904, -909, -91, -910, -960, -961, -964, -965, -966, -967, -968, -969, -976, -980, -981, -982, -983, -986, -987, -988, -990, -991, -992, -993;
0-120-496-593, 0-886-031-501, 9-120-080-129, 9-120-143-036; 9-120-144-205, -206, -207, -216, -217, -237, -281, -282, -290, -292, -301, -305, -600, -601, -602, -603, -604, -608, -609, -612, -615, -616, -619, -620; 9-120-334-324
, 1-192-052-015, 1-192-052-016, 1-192-052-020, 1-192-052-021, 1-192-052-024, 1-192-052-025, 1-192-052-027, 1-192-05-029, 1-197-311-003, 1-197-311-004, 1-197-311-005, 1-197-311-006, 1-197-311-007, 1-197-311-008, 1-197-311-009, 1-197-311-010, 1-197-311-011, 1-197-311-012, 1-197-311-013, 1-197-311-018, 1-197-311-021, 1-197-311-022, 1-197-311-023, 1-197-311-026, 1-197-311-027, 1-197-311-028, 1-197-311-035, 1-197-311-038, 1-197-311-039, 1-197-311-040, 1-197-311-050, 1-197-311-090, 1-197-311-800, 9-191-337-303,
Deutz-Allis 93155548
Fendt X830060022010
Ford 86GB-10316AA, 82BB-10316-AA, E5RD-10316-BA
Fiat  60751135, 60751403, 60751439, 9938171, 9942848, 9942885, 99428884, 9950155, 9960176
GM 90349704, 90349907
IHC 1530372C1
KHD 81211111
Lucas 21221349, UCB403
Mercedes Benz 002-154-4106, 002-154-5106, 002-154-7206, 002-154-7906
Opel 1204256, 1204259, 1204253, 90007041
Porsche 944 603 14100, 944 603 14101, 928-603-153-00
Saab 8571846, 8590549
Volvo 1324617, 1197311028, 1197311090, 1235887, 244332
VW-Audi 068-903-803


If you have a regulator part number that does not correspond, feel free to ask.

Bosch Alternator -- External Fan with 32mm Slip Ring
A 32mm Internal Adjustable Regulator ONLY will exchange correctly with these Voltage Regulator Part Numbers
Audi/Volkswagen 028-903-803A, 049-903-803B, 049-903-803E, 049-903-803F, 052-903-803, 059-903-803, 059-903-803B, 059-903-803C, 063-903-803, 070-903-803A
BMW 1231 1286 073
Bosch 0-192-052-001, 0-192-052-002, 0-192-052-004, 0-192-052-005, 0-192-052-006, 0-192-052-008, 0-192-052-011, 0-192-052-012, 0-192-052-013, 0-192-052-014, 0-192-052-017, 0-192-052-018, 0-192-052-019, 0-192-052-022, 0-192-052-024, 0-192-052-025, 0-192-052-026, 0-192-052-028, 0-192-052-031, 1-197-311-000, 1-197-311-001, 1-197-311-002, 1-197-311-090
Delco 90009353
Fiat 4 474 755, 4 475 296, 4 731 653, 9 927 829, 9 933 186, 9 934 791, 82 302 913
Ford 1477502, 71BB-10316-AA
GM 90009353
Iskra 10-120-110, 11-125-003, 11-125-040, 11-125-049, 11-125-073, 11-125-117, 11-125-121, NRE121301, AER7201, AER1503, AER7207, AER1527
Lucas 01221 152, 21221 347, 21221 373, 21931 009, UCB400
Magirus-Deutz 4 248 4638
Magneti-Marelli 648-080-10, 648-080-11, 648-080-12, 648-081-09, RTT110A, RTT110AB, RTT110ABT
Mercedes Benz 002-154-0606, 002-154-1806, 002-154-2506, 002-154-5806
Opel 1204244, 1204252
Valeo 505-055, NB411


Advantages of an Adjustable Voltage Regulator

These adjustable regultators will do wonders for most Volvo 200, 700, or 900 series charging systems.  They allow you to set your voltage instead of relying on the preset (usually too low) voltage found in most older cars with Bosch alternators.

I have been using the External Adjustable Regulator Kit in my 1984 245 Turbo for several years and I am very happy with it.  Prior to installing it, I was noticing my OEM Bosch alternator was lucky to put out 12.5 to 12.8 volts with no load.  At times, voltage would drop below 12 volts when under load, such as using headlights, heater fan, etc.   I was shocked to discover how much load was generated with my headlights on (higher wattage bulbs), an electric cooling fan running, and a air conditioning or heater fan going.  Voltage frequently dropped so low that my Rockford Fosgate stereo amplifier would cut out.  If you don't have a good voltage gauge in your car, you might be surprised too at what your car is doing.

Another advantage of the remote mounted regulator is that the regulator will run much cooler, especially if the normal alternator position is near the hot exhaust manifold (like in a Volvo 240). You may have already noticed this.... Original Bosch regulators have a negative temperature coefficient that causes the charge voltage to drop as the device heats up.  So a cooler running regulator means better efficiency.
 
After installing this kit, I set the no-load voltage to 14.5 volts and I was amazed at the difference.  My headlights were brighter, my electric primary cooling fan sounded like it almost doubled in speed, and my stereo amplifier worked perfectly.

Different cars can have different levels of improvement according to the state of your charging system.  My car was a good test for this regulator and the improvement was dramatic to say the least.  Your own results may vary depending on the state of your charging system.

Customer Comments:
"
Just wanted to thank you for the regulator and let you know it's working very well.  I'm quite impressed with how well made it is, and how easily the voltage is adjusted.  The dashpot is very smooth and linear in how it varies the voltage."

Installing an Adjustable Voltage Regulator
 (Please read WARNING below regarding installation)

For illustration purposes, I installed an External Adjustable Kit in my son's 1980 242 DL.  Before the installation, I checked the no-load voltage at the battery while the engine was idling and found it to be 13.7 volts (not too bad for an older Volvo).

The first order of business: disconnect the negative side of your battery.

For BEST access to the rear of the alternator in a 240, you should pull the alternator out.  If you have a 700 series, the alternator is up high and access to the back is pretty good.  If you are not confident in your abilities with this type of installation, I recommend you have someone with experience help.  It is easy to permanently damage the regulator (see below damage pic) when installing if you don't know what you're doing.  The brushes are fragile and will BREAK if forced.  But if this happens, the brushes are replaceable.

In the photo to the right, you can see the old internal voltage regulator attached to the back of the alternator.  It's the black box thing (also below left photo).  It's attached by two screws (sometimes slotted, sometimes Phillips)... a very simple removal... no wires to disconnect.  If you are working on a 240 Turbo, you will definitely need to remove the alternator, since it will be impossible to get in behind it while still mounted in place.

Here's a photo of the internal regulator I removed.  It looks like an aftermarket  type.   This 1980 DL (as did many early Volvos) was originally equipped with a factory Bosch external voltage regulator very similar to the one being installed now, except that it was not adjustable.  Somewhere along its life, a previous owner must have "modernized" the car and installed this internal one.
 




Ok, here's the new brush assembly, ready to install in your alternator in place of your internal regulator.  Don't forget to remove the pin on the brush assembly before installation so the brushes will extend as needed.  The pin is only there for shipping.   NOTE: During these procedures it is best not to handle the brushes with your bare hands as the oil from your skin can contaminate them and reduce their life.
 
 
 
 
  

 

Now the new brush assembly is installed in the alternator.  I have securely mounted the external adjustable regulator (the silver metal box near the radiator fan). You can also see the harness connecting the two components. It really couldn't be much simpler unless I came over and installed it for you. The regulator can be mounted anywhere under your hood within the 32 inch reach of the harness (or elsewhere if you opt for a longer harness).

Total installation time for me was about 45 minutes, but a first-timer might be longer.

After reconnecting the battery, I started the car and checked the voltage (measuring at the battery).  The preset voltage for this regulator seemed to be around 14 volts.  I like it a little higher, so I used a small screwdriver to turn the voltage up to 14.5 volts without any accessories on (such as heater fan, headlights, A/C).  The little screw needs to be turned clockwise just a little bit.  Don't over-do it as the screw is very sensitive. Also, do not try to force the screw past its limit as you will damage the regulatorIMPORTANT:  I do not recommend adjusting this regulator without knowing the voltage.  You should use a voltage meter hooked up at the battery to see what you are setting it at.  And please don't rely on your in-dash voltage meter, unless you have verified its accuracy.  Very few I have seen are accurate.  Do yourself a favor and buy an inexpensive digital meter to accurately measure your voltage at the battery.

IMPORTANT:  
An initial FAILURE TO CHARGE can occur on a high mileage alternator (this means WORN) after you install a new brush assembly or new internal regulator
.
  I have seen this occur several times on my own installations.  After installing a new brush assembly, I found that it was not charging right away.  This has happened to a few customers as well.  It is quite puzzling and you will begin thinking you have a faulty regulator.  A classic symptom is having good battery voltage (maybe 12.5 volts) with the engine OFF, and having LESS voltage at the battery with the engine running.

If you have a failure after replacing these parts, the obvious things to check will be your connections at the rear of the alternator. 
1. The BIG RED CABLE is the main power cable.  It goes to the starter motor and then to the battery.
2. The SMALL RED WIRE completes the Battery Warning Light Circuit (light on your dash) and if it is not connected properly the alternator will not charge.  You will know this circuit is complete if you see the Battery Light ON when the ignition key is turned to the 'ON' position with engine OFF.
3. There is a GROUND cable that is attached to the alternator case (usually a small stud with an 8 mm head nut).  The other end will be connected to the engine or alternator bracket.  If this ground is not complete, the above Battery Light Circuit will not function and the alternator will not charge.


If the above connections are good, and still you aren't charging, it is possible there is a less than optimum contact between the NEW brushes and your OLD alternator slip rings. 
When I first saw this I was quite puzzled, but as it turned out the friction ends of the brushes needed some time to break down the old glaze on the slip rings to establish a good electrical connection. So it would seem one cure would be to continue running the engine until the voltage regulator starts working... the theory being that once a good electrical connnection is established the voltage should come up. 

Here's the experience of one customer:
"I took the new brushes out when there was no charge and noticed the contact spot was real small.  It is possible that they need to take the shape of the slip ring and make full contact before a charge appears, at least that is how it looks.
Usually with stock regulators it takes a few seconds for the warning light to go out.  This time it took several tries, a purchase of an unnecessary new regulator and five minutes of determined revving at high rpm to get it.  However, overalll I am greatly happy with this setup, my battery used to discharge all the time.  Just from running fog lights and a radio I had only 11 volts on board.  Now I have 13.8 without load and 12.8 with radio and fog lights.  I would also strongly recommend everyone to install a Voltmeter in addition to this setup."  R.B., (VW Vanagon) Sherman Oaks, CA

Here are some suggestions to follow during installation in well used alternators to help avoid the above condition:
Once you remove the old regulator use some fairly fine sand paper to clean (or "de-glaze") the slip rings.  You can do this by spinning the pulley by hand, while reaching in the back of the alternator with the sand paper.  It is recommended that you use GARNET paper (the orange stuff) only. This is because crocus cloth, emery cloth and silicon carbide paper can eventually damage the slip rings. With crocus cloth and emery cloth, the abrasive material is metallic in origin. It can flake off the paper and get down inside the alternator and can cause internal shorts. With the silicon carbide paper you can have a contamination problem; the silicon can bond with the carbon in the brushes and cause greatly increased brush wear.

Once your slip rings are clean, you can pre-seat your brushes if you like (not required, but a good thing to do if you can).  Wrap some Garnet paper (200 grit or higher) around a small cylinder about the same size as the slip rings (28 mm) in diameter and use it as a tool to slowly wear the appropriate arc into the brushes.  This will help them to seat faster, preventing sparking, poor wear and it will increase the life of the brushes. 

REMEMBER: During these procedures it is best
not to handle the brushes with your bare hands.  I have been told the oil from your skin can contaminate them.   Sounds a bit extreme, but do your best.


Here's a photo of the Internal Adjustable Voltage Regulator in a typical Bosch IR/EF (Internal Regulator/External Fan) alternator from a 740 GLE.  Installation is much easier if the alternator is removed.  The adjusting screw can be seen in the back of this internal regulator.
 
 
 
 
 
 
 
 
 
 
 

WARNING Regarding Installation:
Electrical Parts, such as these special regulators, are delicate and do not hold up well to abuse.  If you are not experienced with this sort of installation, then I STRONGLY recommend you have a professional or someone with experience install it for you.  Otherwise, if you try to force or install this kind of part incorrectly and destroy it, please don't write me and tell me it simply "fell apart" and must have been defective like this customer did.  Forcing parts like these is always a bad idea.

ALTERNATOR TESTING
If you are using an external regulator with a brush assembly like the one pictured, the below Full Field Test method will determine how well your alternator is charging.  In case of a problem, this procedure can help you decide if the alternator is at fault or if the regulator is at fault. This test is standard procedure in older shop manuals.

Basically, you will be bypassing the regulator so a full 12V is applied to the alternator rotor winding. The battery voltage should go to about 16V, so you should  only run the engine just long enough to measure the voltage.

On the external regulator harness I supply with this kit, the wire colors are: D- (BLACK), D+ (RED), DF (GREEN).   The bypass is applied by unplugging the regulator harness at the regulator end and jumpering the D+ (RED) and DF (GREEN) socket pins.   The remaining D- (BLACK) pin is already grounded to the alternator case as it should be.

If you get around 16V or more, the alternator is good and the problem is likely the regulator or other wiring in the car.

The same test can be done with an internal type regulator setup by replacing the brush/regulator assembly with one that has been modified (regulator portion removed) with an internal jumper of the D+ and DF pins. This could be made from an old bad internal regulator unit (just make sure the brushes are still good). 

A good Brickboard discussion on Alternator Wear and Slip Rings:
http://www.brickboard.com/RWD/index.htm?id=725699

ALTERNATIVE MODS TO EXISTING REGULATORS
http://articles.mbz.org/electric/regulator/

OTHER LINKS
But what if I think my alternator is bad?
You might check out the following for tips on diagnosing a bad alternator....
http://www.misterfixit.com/alterntr.htm
http://www.humanspeakers.com/audi/alternator.htm
 

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