Replacing the bearings in a Bosch 90a alternator

Bosch alternator 90a change of brushes

Regulator number Bosch F 00M 145 225Synthesis and disassembly is no special complexities, so will not describe in detail.

The plastic on the photo take off carefully, I prydeljit one side with a screwdriver and it snapped)

There is a big wear on the contact ring, for replacement I bought Cargo 135172. 135r

I took off my NSK 6003DUB rear bearing with a wire stripper without any problems, but with the front bearing NSK B17-102DG38 I had to spend a lot of time, in the end I sawed it with an angle grinder, it slightly damaged the shaft, so please be careful with it!)I bought the rear Bosch F 00M 990 405. 220r, and inside was KOYO 6003RDD

and the front Cargo 140093. 260r, with this even more fun, in Exist brought a box with FAG 6303.C3, and on top there is a sticker with the Cargo number

The minimum allowable brushes in the book 5mm, mine would still fit, but I decided to change, looking on the net ordered Ika 0.1719.1. 50r pair, stated dimensions 4.66.3515.4, but they are bigger than the original!(native

3,6×5,7), so if possible pick up others. The brushes themselves are normal quality, GEBE labeled on the box.

To replace the brushes you have to remove the small cover on the back, it looks like it sits on the ecopsid, I popped it open on all sides with a knife and took it off. Remove all remnants of the eco-psilicon to get to the brush contacts, do it carefully, so that there are wires on the contact pads (I ripped one off).

Next, let’s drill a hole, I used a drill 2mm and drilled right near the wire (the 3rd hole on the photo is far away from the contact)). It is better to leave the part of the wire welded to the aluminum pad. it will be easier to solder.

The new brushes because of the discrepancy in size had to be ground with a file, the wire goes freely into the hole, one soldered to the remains of the old end of the brush, for the other had to use flux for soldering aluminum. Do not forget about the springs, the length of the wire brushes shorten on the spot Trying on the cover, t.к. It has grooves for contacts and if there is too much solder it can be crooked (and it happened to me, but it was too late to change something, the eco-psy quickly dries), we put a good glue on everything and put it in place.We paint the generator in silver color and assemble it)

Checking the Volkswagen Passat B3 alternator

Check in the following order:

Remove in the following order:

replacing, bearings, bosch, alternator

Install in the reverse order from the removal. Adjust the tension of the drive belt before you finally tighten the alternator mounting bolts.

Replacing the bearings in a Bosch 140A alternator

Six months ago I decided to change the overrunning clutch, and I noticed that the bearings in the alternator were starting to make a noise that wasn’t working. I was waiting for another report from Tikhokhodka, but decided to do it myself. How to remove the alternator, here ufty-shkiva-i/ Tihokhod report on overrunning clutch replacement, here tora-s-muftoi/

Unscrew overrunning clutch. 2. Unscrew the two nuts of the plastic cover of the alternator. One nut is 13 mm, the other 15 mm. The 15mm nut can be unscrewed only with a head without a chamfer because the thickness of the nut is only 2mm. So don’t forget to have the head at hand. 3. Unscrew the voltage regulator 4. Unscrew 4 bolts at 8mm of the alternator housing. 5. We disassemble the generator into two parts by lightly tapping with a hammer.(The cover on the overrunning clutch side was the first to come off) 6. Unscrew the rotor from the small bearing side of the housing. 7. Remove the small bearing from the rotor. 8. Unscrew 4 bolts of the large bearing retention plate and remove the large bearing from the housing. Assembling in reverse order. Special tools: 15mm bevel head, small bearing puller, 2 arbors of appropriate size for small and large bearing. By parts: Large bearing 0633A, small bearing 6003DU8.


Sequence of steps

How to change: step by step guide on the video with Комментарии и мнения владельцев from the master

Opinion of the expert Nikolay Gray Experience of more than 5 years Specialization: body repair, customizing, preparation for painting, honing

In other words, if the bearings in an alternator are making strange noises, they need to be replaced, and immediately. Because not only they can fail, but the entire generator. One day it will simply jam, its rotor will stop rotating, and fragments of the splintered cage will damage the alternator windings. Such part can not be restored. You would have to change the entire generator, and that’s quite a lot of money.

Taking an alternator apart, removing and replacing the bearings

After dismantling disassemble and replace the bearing of the generator Renault Logan 1.6. This process usually takes 30-40 minutes, with experienced drivers 15-20 minutes.

  • Remove the brush holder and regulator relay. When qualified repair is carried out at the same time preventive maintenance and check the functionality of the relay. Also check the brush holder for defects, check the condition of the brushes.
  • There are three screws that can be loosened to disassemble the housing in two pieces. A Phillips screwdriver is needed here. Next, use a chisel and hammer to “split” the housing.
  • The reliable and proven way to remove the pulley (suitable for Bosch) is to use an M18 nut and an M10 hexagonal cutter.
  • Put some washers inside the pulley and an M18 nut with a 27 wrench on top;
  • Insert an M10 hexagon or a bit;
  • Use a 10 head to block the pulley;
  • Use a socket wrench 27 to loosen the pulley mount;
  • It is advisable to apply WD-40 to the joint beforehand.

Remove the old ball bearings and install the new ones

  • With the pulley removed, knock the rotor shaft out of the ball bearing bore. This method is not safe, because you can damage the shaft itself.
  • A more effective method (shown in the four photos below):
  • Removing the ball bearing cover;
  • Clamp the outer cage in a vise until it breaks;
  • Pressing the inner cage from the rotor.
  • It is now possible to remove the front pcb. Press it out of the housing from the opposite side. Using a clamp puller.
  • The way to remove the rear ball bearing without puller is shown below. With one or two open-end wrenches, apply force to the bottom end, as shown in the second photo.
  • Immediately mount the new ball bearing in the cover, tighten the four screws. Then press the rotor shaft into the hole and hammer in over a wooden spacer or press down firmly by hand.
  • Install the front pinchwheel on the shaft. For this purpose we grease seating surfaces, put on a detail.
  • Then using a socket head with a diameter to match the inner ring, press the ball bearing into place.
  • Let’s proceed to reassemble the electric alternator of Renault Logan.
  • The pressing force should only be applied to the inner ring.
  • Note that the insertion of the rear bearing of Renault Logan alternator from the new repair kit will require accuracy, otherwise there will be backlash or misalignment.
  • To assemble and install in the reverse order. The complete process is shown on video at the end of the article.

How to disassemble the generator Bosch

All right, I was a little downhearted, I thought. Just go and buy NTN bearings at the most famous among us store exist.It seemed to me a boring and cheap pleasure. Urine hit my head which decided to find SKF bearings by all means, it took almost 3 working days to find.

The difference between them. one with a thermal gap, the other without.

Why so? SKF. for me the most reliable, bought from the suppliers of bearings for companies, not from a dealer, selling “stranger”, stranger brought from where, that’s the logic)

Took the alternator off the car. How it happens this process is described in detail here. you can’t write better than that if you want to)

After all the necessary tools for disassembly, started to gut it:

And now pay attention! You’ll need an 8mm screwdriver to remove the alternator. an extension cord and a screwdriver of some kind, that will make disassembly super duper pussy! Believe me, these 4 bolts are hard to get off even with a head, let alone a screwdriver.

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The stator is fine, make sure the plastic bushing for the rotor bearing in it is intact.

Bosch 90A Alternator Bearing Replacement

But with the rotor you will have to learn a new mystery of love affairs =)

First I decided to unscrew the pulley. On the forum, Valeri used a belt and a gas wrench. I decided to take my chances and clamp the rotor in a vise! Which incidentally did not regret at all. WARNING. If you decide to do the same, do so at your own risk, I have little strength, I did not clamp the rotor hard! We take WD-40, a 24 mm head, a screwdriver and click-click, the nut gave in.

After unscrewing the pulley, removing the cover, I started measuring to determine if there is wear

In my head vague doubts, the generator Bosch bearing Koyo, or I’m a fool or the Germans decided to put their overseas parts.

Damn it, I thought softly What kind of person would have to be such a great person to put such screws back, pre-installed there bearings are not the best quality

Verdict, the alternator’s not pristine. The bearing was jammed, the backlash was hellish, the brushes were fried properly.

Well I thought, it was not I took a screwdriver, picked up the nozzle for the appointment (with slits on 8 faces, as it should be, so that the stuttering of the AUTOMECHANIC BOTTOM that loosened the screws) and tried it:

Of course I failed, even though I couldn’t turn the screwdriver in the splines, I still screwed them down by sheer force, the screws are soft, Valery mentioned it in his report, they were hard and fucking stuck.

There’s a certain consistency in the world, isn’t there?? I decided to leave it for the next day, it will be better in the morning.According to the plans. to drill out the screws, remove the cover, re-press the bearings, pick up screws, or make a new cover with a thread and normal countersunk hex screws, but not this pornography.

I do not know if this tip will be useful to someone, but one thing is for sure. if you do not have a good tool, small tooling. do not even try, better give a master, save your nerves, limbs and time.

Almost a lucky ticket, almost disassembled a genka.

The procedure is applicable to cars:

Volkswagen Passat B5.5 / Volkswagen Passat B5.5 (3B3) 2001 2005 Volkswagen Passat Variant B5.5 / Volkswagen Passat Option B5.5 (3B6) 2001 2005

Volkswagen Passat B5 / Volkswagen Passat B5 (3B2) 1997 2001 Volkswagen Passat Variant B5 / Volkswagen Passat Variant B5 (3B5) 1997 2001

Volkswagen Passat B4 / Volkswagen Passat B4 (3A2) 1994 1997 Volkswagen Passat Variant B4 / Volkswagen Passat Variant B4 (3A5) 1994 1997

Volkswagen Passat B3 / Volkswagen Passat B3 (312) 1988 1994 Volkswagen Passat Variant B3 / Volkswagen Passat Variant B3 (315) 1988 1994

Volkswagen Golf 4 / Volkswagen Golf 4 (1J1, 1J5) 1997 2004 Volkswagen Bora / Volkswagen Bora (1J2, 1J6) 1999 2005

Volkswagen Golf 3 / Volkswagen Golf 3 (1H1, 1H5) 1992 1998 Volkswagen Vento / Volkswagen Vento (1H2) 1992 1998

Volkswagen Golf 2 / Volkswagen Golf 2 (191, 192, 193, 194) 1984 1988 Volkswagen Jetta 2 / Volkswagen Jetta 2 (165, 166, 167, 168) 1984 1988 Volkswagen Golf 2 / Volkswagen Golf 2 (1G1) 1989 1992 Volkswagen Jetta 2 / Volkswagen Jetta 2 (1G2) 1989 1992

Information suitable for other vehicles.

Bosch alternator bearing replacement. VW Vento 1994.c, ADY engine, Bosch 90 amp alternator. 1. Remove the alternator from the vehicle. 2. Unscrew the 3 small screws that hold the cover. 3. Remove the cover. 4. Remove the brushes. 5. Remove four screws that fix two halves of the alternator. They fit a Phillips head screwdriver and 8 mm wrench. 6. Using a flat-blade screwdriver, I used a knife, we separate the alternator into two parts.

Accessing the rear bearing. Remove plastic cover from it.

Pull off bearing with puller. The second bearing the puller failed. Had to run out for another, more serious.

Unscrew the nut fixing the pulley, t.к. I couldn’t find a sprocket/hexagon socket for 8 in 4 stores, so I used a gas wrench.

Next I removed the four screws that secure the bearing cap.

Using puller I pushed out the bearing with rotor from the pulley.

Pull the bearing and circlip off the shaft with a puller. Had to sharpen the legs a bit to get under the bearing.

All bearings removed. I put the rotor in the freezer. Temperature.24 degrees. In half an hour I got it out and both bearings popped onto the shaft just by hand with a whistle. Slightly through the tube to put them on more tightly. Don’t forget the retaining ring.

Heated the front cover over a gas stove and easily slipped it onto the bearing. I cooled it with a hair dryer to prevent heating the bearing too much.

Inserting the plastic rear bearing cover into the back cover. I wet it a little and put the two halves of the alternator together.

Remained to tighten the 4 screws tightening the alternator, put the brushes, put the cover and screw it on.

As to generators Bosch 65A on the second Golf, there such Focus will not pass. Front bearing with the upper part of the alternator housing refused to be removed together with the housing.Broke it in small pieces in two places.Had to drill bolts, and unscrewed with a broken drill inside.When reassembling, new screws were put on the nut, so that it was possible to securely torque.I used FAG bearings, 203 and 201 respectively. Do not skimp on the bearings.There was also a problem with the M5 110mm screws.One twisted the slits, bought 90 mm bolts in hardware, no problem.Probably makes sense to pour WD40 overnight.

Front bearing SKF 6303, SKF rear bearing 6203. Be sure to buy with caps.

If it is an old style alternator, the rear bearing will be 6201. In the author of the topic on the photo of the generator you can see that the pulley under the V-belt and most importantly the rear bearing is big and is between the rings and the winding of the rotor. And the older alternators have the pulley under the crescent belt and the bearing is twice less and is located at the end of the shaft. One more note (missed) cooling impeller near the pulley, not inside. Here, in short, the “old” alternator. By the way, when replacing the rear bearing, it would be a good idea to replace its “bed” as well. The old and new alternators are also different in their upper mounting.

It happens that the main reason of friction of the rotor against the stator is the wear of the outer surface of the plastic bushing of the rear bearing, which is accompanied by a characteristic noise. Repaired by increasing the size with a good quality duct tape. The main thing is to accurately adjust the size to a snug fit. Has been running trouble free for over 4 years.

Replacement of the collector rings in the generator Bosch: Remove the rotor, remove the rear bearing, note the distance from the rings to the bearing seating (e.g.2mm).One wire is soldered at the bottom and the other is soldered at the top of the slots under the rings.е. to the upper call.ring). Use a sharp chisel to cut out the soldering point with a piece of coll. Rings and carefully solder them off the wires, taking care not to cut them. Remove the textolite backing and strip the shaft. Press in new rings (with the projection downward)!), paying attention to the distance to the pins.,put the wires in the slots and solder them thoroughly. Remove surplus solder with file and grind it with emery board.Check the winding resistance 2.8-3.5 Ohm and check that the wires are not shorted to the frame.Push new bearing all the way in. Rotor ready!

After a gas wrench the pulley can begin to eat your belts with great appetite. Just TITS to the rotor! Nut is perfectly unscrewed with ring spanner or L-key at 24 and M10 spline (star). A gas wrench is not really an automotive tool To remove the front bearing (the one with the biggest one), I used a cage puller. But to use it I had to bend the fan blades. The other pullers either wouldn’t go through or broke. Yes, it is better to unscrew the bolts that connect the two halves of the alternator housing with an impact screwdriver. At first I tried it with a regular Phillips head. I ripped all the slits to hell. Also soaking it for a few days with “liquid wrench” did not help. I had to run to the store for a percussion screwdriver.

I tell you that vinegar (if you have essence, it’s even better) is better than WD 40. So do not bend and beat this pulley, tear edges of the nut and break hexes. I put it vertically and poured directly into the pulley to cover the nut, you can use a sprayer, put it on the balcony, otherwise the room is bad for breathing. The main thing is to watch that it does not dry out, regularly moisten it if necessary. There is one more radical method, it is heating with a gas torch, but you can burn the generator that way.

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If you can not find information on your car, look it on the cars built on the platform of your car. There is a high probability that information on repair and maintenance is also suitable for your car.

Bottom line: I give you a “fat” score for design and build! Managers defeated the designers, and production workers ended up defeated!

Choice and search of a bearing for an alternator of the car

Many motorists who drive older cars with mileage of more than 100 000 km, probably faced with the need to repair or routine maintenance of the alternator. It is known that bearings are subject to the highest wear in the whole construction of an alternator. Diagnosing failure of an alternator bearing is often not at all difficult. If an extraneous hum has appeared during engine operation, which intensifies when the number of revolutions is increased, the alternator bearing may be one of the sources of its origin. For more accurate diagnosis, you need to loosen the alternator belt tensioner, then remove the belt and release the alternator pulley. Then you start the engine and if the hum has disappeared, then the reason is clear It is necessary to replace the bearing of the generator.

Replacing the bearings of an alternator is a time-consuming, but moderately complicated technical operation. Therefore, many motorists carry out repair and maintenance of the generator themselves, without resorting to the services of car repair shops. Such decision has both pluses and minuses. The main advantage is that an independent replacement of the alternator bearings saves a certain amount of money. The motorist will bear all expenses only for acquisition of bearings. The disadvantages are the fact that during the works you will definitely need a special tool, such as a hydraulic press and various detractors, without which you will have to sweat a lot and show ingenuity. Another important point is the right choice of bearing on an alternator. And DAS LAGER specialists will help you to understand this difficult question.

  • Remove the alternator from the vehicle;
  • Unscrew all fasteners by disconnecting the stator, rotor, diode bridge, etc.д.
  • Dismantle the front and rear alternator bearings;
  • Identify bearings by their marking. If the markings are missing, perform identification by taking off the mounting dimensions;
  • Buy the right bearings from a trusted supplier;
  • Install the new bearings in their seats and assemble the alternator in the recommended manner.

And if the process of disassembly and reassembly of an alternator does not cause any special questions, it is not so easy to find the right bearing. Below we give the most common variants of bearings used in alternators of different makes of automobiles. In a standard alternator, there are two bearings, one in the front and one in the rear. The front bearing of the alternator is usually the more powerful bearing. This is due to the fact that it is the front bearing that carries the brunt of the load. This load is caused by the tension of the drive belt on the alternator pulley. The pulley transmits the load to the shaft and the shaft in its turn acts on the bearing. Different manufacturers use different bearings in the production of generators. We have identified the most popular of the total number of. The following bearings are often installed in the Russian models of alternators:

6302-2RS has dimensions 15x42x13. Its domestic equivalent is designated as 180302 or simply called 302 closed. This bearing is used as a front bearing in older alternators. One of the places where it is installed are the alternators of VAZ2110 and VAZ2112 cars. 6303-2RS has the dimensions 17x47x14. Its domestic equivalent is designated as 180303 or simply called 303 closed. This bearing is used as a front bearing on newer alternators. One of the places where it is installed are alternators of VAZ2110 and VAZ2112 cars. 6202-2RS has dimensions 15х35х11. Its domestic equivalent is designated as 180202 or simply called 202 closed. This bearing is used as a rear bearing on the newer alternators. One of the places where it is installed are alternators of VAZ2110 and VAZ2112 cars. 6203-2RS has dimensions 17х40х12. Its domestic equivalent is designated as 180203 or simply called 203 closed. This bearing is used as a rear bearing on the newer alternators. One of its installation places are alternators of VAZ2110 and VAZ2112 cars. 6003-2RS has dimensions 17x35x10. Its domestic equivalent is designated as 180103 or simply called 103rd closed. This bearing is used as a rear bearing in an alternator. One of the places where it is installed are the alternators of VAZ2110 and VAZ2112 cars. 62202-2RS has the following dimensions 15х35х14. Its domestic counterpart is designated as 180502 or simply called 502 closed. This bearing is used as the rear bearing in the alternator. One of the places where it is installed are the alternators of VAZ2110 VAZ2112 VAZ2115 cars.

Alternators from Bosch are common on imported cars. The bearings in these bearings vary with the characteristics of the alternator itself. Thus, for example, in the widespread alternator Bosch 14V 53-98A 8200 43 81 48 0124 415 038 (installed on many foreign cars of economy class) bearings 6003-2RS (rear) and 6303-2RS (front) are used. This pair of bearings is found in many imported alternators. There are also variations where the rear bearing is designated 6000-2RS and the front bearing is 6203-2RS. Experts are unanimous in opinion that quality imported bearings should be chosen when replacing alternator bearings. Optimal option would be a bearing from DAS LAGER Germany. These bearings will last a long time and are reasonably priced. If you have any difficulty in choosing the right bearing, do not hesitate to call our managers, they will help you.

Bearing sizes and manufacturers

Before replacing the bearing with a new standard product, you need to buy it. The marking of these standard consumable parts is complex, the numbers in it are deciphered by special tables. over, the GOST 3189 bearing designations do not coincide with the foreign manufacturers’ markings, so the user must be aware of the following nuances:

  • marking consists of three parts (main, left, right), and the blocks within them;
  • in the left and main unit, the blocks are arranged from right to left, and in the right unit vice versa, from left to right;
  • In automobiles, the front bearing of the alternator most often has the main part designation 302 or 303, and the rear bearing 202 or 203;
  • Usually you use deep groove ball modifications with code 0 (0302 or 0202) or deep groove ball modifications with code 6 (6303 and 6203);
  • so for these parameters the dimensions can be deciphered from the lower table;
  • similar markings are used for the bearings of foreign manufacturers.

The suffix (right side of the marking) of imported bearings contains additional information. For example, letters and numbers can indicate:

  • 2RS and RS. two-sided and one-sided rubber seal, respectively;
  • N and NR are keyways on the outer ring without and with a latch, respectively;
  • J. steel casing;
  • Z. one side protection by sheet metal without seals.

The main problem of the motorist in self-repair is the variety of bearing sizes inside the alternator:

  • Guessing the marking before disassembly when the car is still running is difficult;
  • after dismantling and disassembling the generator, the dimensions and markings are known to the owner, but he has to go to the store in another car;
  • in some stores sellers practice a convenient system. the car owner takes 4 bearings 202, 203, 302 and 303, returns two of them back.

Due to the variety of brands and models of cars, different capacity and construction of alternators, it is easier to study the manual before replacing bearings. The marking of these standard parts and adequate options for replacement are listed there.

The most expensive are considered to be bearings of manufacturer FAG. 450 (6303 modification) and SNR. 400 (6203 ZZ). Half the price for bearings of Koyo. 200 for 6303C3, NTN. 180 for 6203ZZ and Nachi. 150 for 6203ZZ. Set of standard items for VAZ 2114 (16 volt) alternator KZATE from Chinese manufacturer CU costs 1100. By default this alternator is completed with Chinese SKF 6202 and SKF 6303 consumables (both with 2RS suffix) at the factory.

In the old VAZ 2110 alternator is completed with bearings 302 and 202 2RS, in the new alternator with a different shaft, you will need standard products 303 and 203, respectively.

Repair of an alternator Bosch Audi A6 C4

This material is fully applicable for 120A alternator repair.

What we need before we start:

We use 12-sided bit for 10, it is not a common tool and it is not found in basic toolkits.

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A socket wrench for 24, also for removing the pulley.

Bearing puller, probably a LARGE bearing puller, I needed because I couldn’t get the front bearing off any other way.

A big puller, I need it, you may not need to.

Something like a shaped screwdriver, a head for 8 and other small items I think are in any tool kit.

Check the alternator plastic bushing in the cover on the contact ring side! Covers often break from time and the bushing goes in them.

Precautions: 1. Remember that for some reason, the rotor shaft of the generator is made of rather soft steel, it can easily bend, deform, and it is easy to score threads on it from the pulley side. So: no hard hitting with a hammer, no vise, only pullers. The thread side of the puller should have a ball or bolt as a stop before putting it on to avoid licking the thread and then you will not be able to screw the sheave nut on.

2. All operations with armature (or rotor) wiring should be performed with utmost care when replacing slip-rings, if a piece of copper wire breaks off at the root. there will be grief.

3. The stator wire should remain in its factory lacquer, otherwise there may be a breakdown on the mass and the generator when the engine is not running will be one big leakage current (I have one such lying around, in memory). Therefore, the removal of the rotor from the housing should be done with due care.

4. When assembling the housing of the alternator, there is a danger of crimping 4 long thin bolts, just tear some of them. I had such a case, and only thanks to my dad’s skill was it possible to remove the remains of the bolt. The disassembly can be divided into 4 basic operations: 1. Removing the pulley 2. Unscrewing the housing 3. Removing the rear bearing 4. Removing the front bearing

To remove the pulley, you need to unscrew the jam nut and pull it off with a pulley puller. To do this, the axle is fitted with a CR10 12-point bit inserted in a socket 8 with a screwdriver clamped in a vice. Then the nut is squeezed with a ring spanner and a tube put on it.

Fix the axle, using a 12-point socket and a screwdriver in a vise.

Under the nut we find a spring washer. The 12-point bit can be removed from the axle without taking it out. It was very useful to clamp it in a vice and use a puller. After that you can remove the pulley with the pulley puller.

Without a sprocket the pulley nut is easy to unscrew with an impact wrench, I just put the belt on the pulley and hold it by hand.

The pulley does not have to be unscrewed on the assembled alternator. you can do it by halving the alternator and clamping the rotor in a vise. it is easy to unscrew with a screwdriver and a 24 mm head

Remove the pulley with a pulley puller

Remove all unnecessary things from the generator:. the back cover with 3 screws and 4 plastic stoppers

The rear cover has 3 self-tapping screws and 4 side stoppers

Then loosen the 4 screws on the front cover on the pulley side. They hold the front bearing cover from the inside. The screws are nasty, they stick to the aluminum housing, and the half countersunk head is not at all conducive to easy unscrewing. It is recommended that the screws be tapped out before unscrewing.

replacing, bearings, bosch, alternator

I unscrewed the front bearing cap after I had pressed it off the rotor, and then knocked the bearing out of it. I used an impact screwdriver to remove the cover screws, it’s more convenient when the cover is removed from the rotor.

Front bearing cover screws

And finally unscrew the 4 long bolts fastening the hull halves.

If the alternator was new or so-new, it should have fallen apart into two halves by now. But this stuff due to temperature fluctuations and aggressive environment had time to be covered with aluminum salts and get stuck to everything with which there is contact. You need a wide screwdriver/screwdriver to pull apart the halves of the housing. The rear goes together with the stator and diode bridge and is removed from the rear bearing.

The rear bearing is in a special plastic sleeve, so it’s easy to separate from the housing.

The front end remains with the rotor (armature) on the front bearing.

It’s easy, I put the bolt in, put the puller on it, and yanked it off the axle.

The front cover did not come off, had to take a big puller and peel it off. Then used a small puller to separately remove the bearing from the axle. The front bearing on the rotor is not only supported by an inner ring, but also by a thrust washer pressed on the axle.

Removing the rotor with front bearing from the front cover

Front cover removed, note the layer of oxide that interfered with disassembly.

Disassembling of the catenary

First you need to separate solder copper wires from the collector pins with a very thin screwdriver or knife, without breaking the wires. After they are separated, take them out from under the plastic and you can remove the manifold. Put a bolt of suitable length at the stop and use a bearing puller to remove the rings from the shaft.

Slip Rings, you can see the plastic wrench at the base for proper installation

Bosch alternator disassembled.

By the way the roof rack for Audi a2 can be found at the link on the website There’s a huge selection of trailers and trunks for many cars.

Installing the slip-ring (manifold)

The collector has a special wrench along the circumference, the rotor has a notch for it, for proper installation. Once I managed to mix up the position and ended up with the manifold, because in one piece it did not come off.

Manifold seating on the rotor, wrench on top right

On my third alternator I decided to press the rings in a vise. Pressed. Then I look at it: I bent thin tail of the axle, and now rings have runout. I had to straighten the axle on the machine, the runout remained, but it was a couple of tens of millimeters.

The axle is very soft, it is very easy to bend, I strongly recommend not to press it.

The manifold is hammered very lightly through a soft spacer (wood), so as not to beat the end. Then you put the wires in the grooves and solder them well.

The rear bearing with a tube of suitable diameter (I used the long head from my tool kit) is also pressed onto the axle.

The front cover should be cleaned from the inside with sandpaper to rub off all the aluminum salts and oxides, after that the body will fit without any efforts, as if it was new.

The front cover, there are things on the sides that prevented it from separating from the stator

And here you can see why was not removed the front bearing, it is corroded, aluminum alloy rusts in a different way 😉

I first pressed the front bearing (also by light hammering) into the front cover, then covered the bearing with the cover and tightened the 4 half countersunk head screws. After assembling the front cover, put it on the axle and press it on.

Pressed and assembled front bearing

Assemble the housing with the same long head and light hammer blows.

Stuffing the front cover with bearing on the rotor of Bosch Audi A6 C4 alternator

Then you need to press the thrust washer, on one side there is a step on it, put it towards the bearing using this step.

Stuff the thrust washer, stepped to the bearing

After that assemble the case and tighten the long bolts. Pull it carefully, I in the first alternator broke one of the bolts, you can put it on a threaded sealer, so it does not unscrew like I did.

Installing the pulley and the dodger on the Bosch alternator

It is left to put the pulley, solder brushes on voltage regulator, put voltage regulator and the rear cover. Before installing the voltage regulator, it is recommended to grind all contacts with fine sandpaper.

Stuff the alternator pulley AFTER the thrust washer

tighten the nut for 24, the same way we unscrewed it in the first part

Seems to be all the operations and all the nuances. Bosch alternator work on Audi A6 C4 completed

Replacement and service of brakes of Audi A6 C4

The problem: worn discs, worn brake pads, loss of brake properties