Alternator Slip Ring Wear

TheKid760

Member
Joined
Mar 1, 2012
Location
San Diego, Ca
TDI
1999 MK4 Golf
Hello everyone,

Ive been a lurker for awhile now, on my second ALH, but haven't posted much.

My battery light went on, voltage was low at 11.6, I had alt tested and the machine diagnosed it as faulty regulator.

I pulled it apart and found the brushes to be worn:





and bought a new regulator with brushes for $39, but now I'm wondering how much wear on the slip rings is acceptable before replacement warranted? As ideally I'd like to get my car on the road as fast as possible, yet dont want to have to redo this again in 20k miles. Car has 190k on it and the alternator apperas to be original.





I found these videos on replacing Valeo alternator brushes, slip ring and bearings and think this is within my realm of ability.

Part 1:

http://youtu.be/aVvPzwtxdrM

Part 2:

http://youtu.be/f56-26I6idc

Slip Rings:

http://www.ebay.ie/itm/NEW-REPAIR-K...cles_CarParts_SM&hash=item25753958e1#shpCntId

http://www.maniacelectricmotors.com...m00cm0710111&gclid=COTQu4Dw0sMCFRRgfgodc0YAoQ

http://www.ebay.com/itm/Valeo-OEM-Alternator-Slip-Ring-AUDI-VOLKSWAGEN-SEAT-SKODA-/171329240614


where can I find the bearing in the states?

One of these?

http://store.eurtonelectric.com/metalbearings-8.aspx
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
The upper one is almost worn through, your rotor's junk.

I'd just look for a junkyard alt that looks fresh. Return the regulator you bought and you'll have plenty of money for the junkyard alt.
 
Last edited:

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
Well Kid I wish you luck. Honestly I applaud your bravery at tackling this job. I had never thought to replace the brushes rather than the whole regulator, but why not? If you want to jump in and try, good on you.

NAPA has a 6202 bearings, but the picture I saw was unsealed. You might want to talk with them about it and see if they can get you a sealed bearing.

It looks like for less than $30 and some of your time, you can give it the old college try. If it doesn't work, you are only out a little bit.
 

Alchemist

Veteran Member
Joined
Nov 3, 2007
Location
Lethbridge, Alberta
TDI
'04 ALH Golf
The OP has a new regulator, so brushes are not an issue.

The slip rings are badly worn, but new slip rings are available for a modest price and are easy to replace, so why scrap the whole alternator?

Bearings should be available at any decent auto parts store or industrial supply company. The sealed ones will have a 2RS(2 Rubber Seals) suffix to the 6202 or 6303 number.
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
Thanks. I knew there was some suffix to the 6202 for sealed.

Not that I will remember the next time, but still...
 

TheKid760

Member
Joined
Mar 1, 2012
Location
San Diego, Ca
TDI
1999 MK4 Golf
Yes the regulator was only $39 with new brushes and brushes were $7 so I just ordered the reg. ill find the bearing online and order it today with the slip ring.

Thanks for the info on the bearings.


Misspelling courtesy of my fat fingers...
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
metal ones are just shields not actually seals

good luck
junkyard alt for $50, or $80 in parts into your alt
you're making the same decision I always make
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
But what does the junk yard alternator need? That's where I get hung up. It may need the same thing so then you are into it for $130.
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
But what does the junk yard alternator need? That's where I get hung up. It may need the same thing so then you are into it for $130.
usually nothing

because alternators last for just about forever, and a gas motor one'll have less wear on the overrunning pulley
Usually if you look at car-part.com one place'll have 5 on the shelf, go there and pick out the freshest looking one. Or go to u-pull it and grab one with reman stickers on it.

My truck's one went out a bit ago, same issue, slip ring wore through to plastic, it had 300K miles in the oilfield and a farm. grabbed one off an explorer and it's even got a lifetime warranty from the JY, if it dies, just drag it in and they'll give me another.
 

TheKid760

Member
Joined
Mar 1, 2012
Location
San Diego, Ca
TDI
1999 MK4 Golf
Call me what you will but I'd rather spend $80 on trying to fix it properly myself and risk failing and having to buy a parts store alt than gambling on a scrap yard part.

Junk yards have their purpose, but for me it's for cores, unavailable parts, or parts to be used on something they were never intended for.


Misspelling courtesy of my fat fingers...
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
eh, 'sall good
I could spend a few hundred on an upgraded clutch set, but instead I'm piecing together junk that might work, lol
 

turbocharged798

Veteran Member
Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
Picked up a 120A alternator that supposedly came off a 90K 1.8t for just 30 bucks from a local junkyard. Brushes are almost gone and the slip rings are pretty worn too. I bought it as a core so I really don't care much. Good alternator rebuild how-to maybe? I will be rebuilding it someday just to keep it on the shelf as a spare.
 

TheKid760

Member
Joined
Mar 1, 2012
Location
San Diego, Ca
TDI
1999 MK4 Golf
I bought parts all from here:

http://www.maniacelectricmotors.com/

- NTN Bearing Dimensions : 53500 $10.99
15mm ID x 35mm OD x 11mm W

- Slip Ring Valeo 710111 $8.99
Alternator ID 6.60 & 8.85, OD 14.90, Total length 48.30mm

- Alternator Brushes 7308105 $2.99
14mm L, 6.5mm W, 4.5mm H


Misspelling courtesy of my fat fingers...
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
For what it's worth, I've been running a 90amp Bosch using a slip pulley for the last couple of years without any problems .....

OP, thanks for the info as to where you sourced the parts!
 

TheKid760

Member
Joined
Mar 1, 2012
Location
San Diego, Ca
TDI
1999 MK4 Golf
Sorry its been so long, New baby among other things. But I did a back half rebuild on the alternator and all has been well approx 7-10k miles so far.
I need to write a how to but honestly just watch the videos i first posted, those were extremely helpful. So I'll just post a few pictures and brief captions:
Voltage Regulator with brushes:

Bad Brushes!

Carefully cut crimp but leave as much exposed to solder to as you can, one cut and one not in picture:

Pull bearing:

Remove plastic cage and all epoxy very carefully in center:

Voila!, & now carefully uncrimp wire:

Smash tip slightly in vice and cut plastic but not the shaft in center, then get creative pullin it off:


Gently tap new slip ring on after cleaning shaft till fully seated:

Carefully crimp slip ring to wires:
 

TheKid760

Member
Joined
Mar 1, 2012
Location
San Diego, Ca
TDI
1999 MK4 Golf
Put cap back on and epoxy in place well to cover wire:

Drive new bearing on till seated:

Buy 1/4 copper sleeves from ACE Hardeware or wherever to aid in soldering wires, then solder well:


Get out multimeter to check repair:



Put regulator on:

The black OEM rear cover will have to have some plastic dremeled out to fit new regulator, no big deal.
Now bolt on and use the money you saved on buying me beer or go fast parts...
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
I'm wondering why you didn't pull the armature out. That way you don't have to break the rectifier connections and you can replace the other bearing that sees more load.
 

TheKid760

Member
Joined
Mar 1, 2012
Location
San Diego, Ca
TDI
1999 MK4 Golf
A few reasons i didn't replace the front bearing. The bearing had no discernible play or noise, the brushes were my alternators problem. I had to remove the rear bearing to replace the slip ring so it would've been unwise to reuse old bearing. And time, I was in a rush as I needed my car back and didn't have access to a shop press in the event the bearing didn't want to come off easily. Also from what I read and how it appeared to me there wasn't a way to do it otherwise.
Those bolts in the center of the case hold the armature to the front case, and the way the rectifier connections were I didn't see how the front could come off without cutting them.



Also if anyone wants to know just how bad their slip rings are worn I measured the new ones:

 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
I understand. Time wasn't a problem when I did mine. I replaced the brushes rather than the whole regulator assembly which was a beeech.

I do hate replacing good bearings. You never know if the new one is going to fail; same with tensioners, water pumps, idlers...

Anyway, for future reference, the case comes apart without removing the rectifier. The front bearing is a slip fit on the shaft. You do need to remove the pulley so you need those tools.

At least that's how my '98 was.
 

993er

Veteran Member
Joined
Oct 10, 2013
Location
Canada
TDI
None
A few reasons i didn't replace the front bearing. The bearing had no discernible play or noise...
For the record, it is the front bearing (the one at the pulley) that takes the most load which is why it is usually larger than the other bearing.
 

csstevej

Top Post Dawg
Joined
Aug 12, 2004
Location
north nj
TDI
2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,gluten for punishment got another tdi 2001NB,another yellow tdi NB
Nice write up.
Do you know if there was a kit for this in the U.S., or do you need to go over seas for it?

It would be nice to get everything with one click here in the U.S.

Need to make a spare alt, got 3 of these cars running around all with high mileage.....it's a matter of time lol.
 

993er

Veteran Member
Joined
Oct 10, 2013
Location
Canada
TDI
None
Question - Are these slip rings shot?
For the electrical part, did you measure the resistance between the slip rings? What is the spec for your particular alternator? I just have the alternator off my BMW motorcycle and the rotor resistance spec is 3.4 Ohms. My guess is you should be in that ball park and certainly not an open circuit.

There should be an open circuit from each slip ring to ground.

For the mechanical part, when a slip ring is extremely worn, you will see a deep groove in them made by the carbon brushes. Not an issue if they are smooth and the rotor passes the electrical tests, but its just a matter of time. Slip rings are only so thick...a couple of millimeters.

You should clean the slip rings with a cloth and lacquer thinner or acetone.
 
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