... too late the hero for Gregg (sorry) but, I'm with John on this. the voltage regulator on the back of BOSCH alternators is replaceable at only a fraction of the cost of an alternator. 2 screws, usually slotted, or 7mm socket - less than 1/2" of magnets is the end of service. new are 3/4" to an inch beyond retaining springs. hope this helps someone drive happy ...

--- On Mon, 10/31/11, John Rodgers <inua@CHARTER.NET> wrote:

> From: John Rodgers <inua@CHARTER.NET>
> Subject: Re: Alternator Troubleshooting
> To: vanagon@GERRY.VANAGON.COM
> Date: Monday, October 31, 2011, 11:22 AM
> If you have an alternator that is
> showing a light or nor performing
> properly - of course first check it out. Next step short of
> buying a new
> one - take it somewhere and have it bench tested. If it
> comes back bad -
> check those brushes and replace if worn - then re-test the
> thing. Many
> times the alternator will then test good.
> 
>   I have three vans. I had alternator issues and two
> were down. I took
> them off the vans plus a used spare in a box - over to my
> FLAPS and they
> benched checked all three. All three bad. At the time, I
> didn't have the
> money to buy rebuilt alternators - so I popped the
> rectifier/brush
> holder out  and usre enough - all three had completely
> worn out brushed.
> I then put new rectifier/brushes in all of them. Took them
> back to the
> FLAPS. Two alternators worked, the third didn't. But, for
> just a few
> dollars I was able to get all three vans back up and
> running.
> 
> Under most circumstances I would not buy an alternator that
> tested bad
> until I checked out the rectifier/brushes situation. Like I
> said before
> - $15 vs $125 or more for a rebuilt.
> 
> Just my $0.02.
> 
> John
> 
> John Rodgers
> Clayartist and Moldmaker
> 88'GL VW Bus Driver
> Chelsea, AL
> Http://www.moldhaus.com
> 
> 
> On 10/31/2011 8:59 AM, Larry Alofs wrote:
> > I once took a questionable Bosch alternator from a
> SAAB 900 to 4
> > different FLAPS in the Chicago area for bench tests.
> >    Two places said it was good; two said it
> was bad.  They used various
> > types of machines, some computerized, some not.
> > The last place seemed the most professional and
> knowledgeable and they
> > said "bad".  I bought a rebuilt from them and
> they were right.
> >
> > Larry A.
> >
> >
> > On Sun, Oct 30, 2011 at 9:50 PM, John Rodgers<inua@charter.net> 
> wrote:
> >> When alternator lights start showing in any stage
> of light-up - after
> >> checking all leads, connections,  VOM meter
> readings, etc, BEFORE
> >> putting in another alternator, I pop the
> rectifier/brush holder out and
> >> see if the brushes are worn out. Most times that's
> the problem. Replace
> >> and you are on your way. I keep a spare set in my
> emergency parts box.
> >> $14-$15 or so beats the heck out of $125 or more
> for an alternator. If
> >> you have your alternator benched checked at your
> FLAPS and it shows bad
> >> - DO NOT believe them. Put in the spare
> rectifier/brush holder with new
> >> brushes - then have them check it. Chances are
> pretty darn good your
> >> alternator will now check good!  It may not
> check good - but it also
> >> may. Personal experience with my FLAPS.
> >>
> >> I do go to the trouble of cleaning up the copper
> contact surface in the
> >> alternator where the brushes ride with a little
> piece of worn-out
> >> wet/dry sandpaper by holding the paper against the
> copper surface and
> >> simply turning the shaft. Doesn't take much. If
> there are bad ridges and
> >> grooves in the copper - then the alternator
> probably should be replaced.
> >>
> >> You can get away with this once in the life of
> alternator, but when you
> >> go to do it the second time, it gets really dicey
> and will probably fail
> >> shortly after the doing of it.
> >>
> >> John
> >>
> >> John Rodgers
> >> Clayartist and Moldmaker
> >> 88'GL VW Bus Driver
> >> Chelsea, AL
> >> Http://www.moldhaus.com
> >>
> >>
> >> On 10/30/2011 5:30 PM, Gregg Carlen wrote:
> >>> Well, turns out to have been a bad alternator
> after all.
> >>>
> >>> I found a reference online that said to check
> for continuity across the
> >>> two contacts whet the brushes touch. After
> removing to voltage
> >>> regulate/contacts, sure enough; no continuity
> on the contact points. Double
> >>> checked against the rebuilt one i just got
> from FLAPs and it showed
> >>> continuity.
> >>>
> >>> Ran down to the local Army base to borrow
> their impact wrench and swapped
> >>> the pulleys.
> >>>
> >>> Installed the remanufactured alternator,
> started the van and 'presto', the
> >>> battery light is off.
> >>>
> >>> Voltage between terminals B and D remained
> about 7V, but the B to housing
> >>> and D to housing showed 13.4V. Same at the
> battery connections.
> >>>
> >>> Back in business.
> >>>
> >>> On Oct 30, 2011, at 4:06 PM, Roger
> Whittaker<rogerwhitt1@GMAIL.COM>
> >>>   wrote:
> >>>
> >>>> Dear light up your life
> >>>>
> >>>> Been my experiance with a variety of
> vehicles that those symptoms lead
> >>>> to a new alternator if the wires are all
> I'n place
> >>>> Good luck
> >>>> Regards
> >>>>
> >>>> On Sunday, October 30, 2011, Jim
> Felder<jim.felder@gmail.com> 
>   wrote:
> >>>>> I quickly realized
> >>>>>
> >>>>>> that the pulley’s were different
> between the alternator in the van and
> >>>>>> the
> >>>>>> rebuilt one in the box, so no-go
> for a quick and easy swap since I
> >>>>>> don’t
> >>>>>> have an air compressor strong
> enough to power an air-wrench to ‘bump’
> >>>>>> the
> >>>>>> retaining nut on the pulleys.
> Tried holding it with a vice and such,
> >>>>>> but
> >>>>>> really it’s on there tight.
> >>>>>>
> >>>>> You can hold the alternator body in a
> vice, gently and padded with
> >>>>> cardboard, and hold the pulley with an
> oil filter strap wrench while you
> >>>>> put a socket on the nut.
> >>>>>
> >>>>> Jim
> >>>>>
> >>>>>> So, some quick testing with a
> voltmeter:
> >>>>>>
> >>>>>> Test 1: with the engine running, I
> put my positive lead on terminal B
> >>>>>> and
> >>>>>> the negative lead on terminal D.
> The voltage was 7.1V. Battery light
> >>>>>> still
> >>>>>> on dash.
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> Thinking this is a bad voltage
> regulator or brushes, I pulled the
> >>>>>> voltage
> >>>>>> regulator out. A little grimey at
> the metal contacts, but the brushes
> >>>>>> looked fine. Cleaned the grime off
> and re-installed the regulator.
> >>>>>> Restart
> >>>>>> the engine and check voltage
> across terminals B and D and I get 7.1V.
> >>>>>> Battery light still on dash.
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> Just for kicks, I pulled the
> regulator out again compared it against
> >>>>>> the
> >>>>>> one in the new alternator from
> FLAPs and they look identical
> >>>>>> physically.
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> Test 2: Installed the new voltage
> regulator into my old alternator.
> >>>>>> Started
> >>>>>> the engine and tested across
> terminals B and D and I get 6.9V. A few
> >>>>>> other
> >>>>>> measurements at this point (wish I
> had taken them in previous tests):
> >>>>>>
> >>>>>> Terminal B to alternator housing:
> 11.75v, dropping to 11.5v after about
> >>>>>> 30
> >>>>>> seconds
> >>>>>>
> >>>>>> Terminal D to alternator housing:
> 4.57v
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> So, given that information and
> testing, I’m thinking either I have a
> >>>>>> bad
> >>>>>> alternator (diode, perhaps) or
> I’m chasing down the wrong path
> >>>>>> altogether.
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> One other caveat to mention: on my
> original alternator, the suppression
> >>>>>> condenser was not mounted the same
> as the new alternator from FLAPs
> >>>>>> (which
> >>>>>> was connected to terminal W and
> the alternator housing). Mine has had
> >>>>>> the
> >>>>>> connector cut off and mounted to
> Terminal D, and the condenser itself
> >>>>>> had
> >>>>>> the hole enlarged and mounted to
> terminal B. Don’t know that this would
> >>>>>> cause an issue, but thought I’d
> mention it. It’s been this way since I
> >>>>>> acquired the van earlier this
> year.
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> Any thoughts or advice on other
> things to check? Or, next steps to
> >>>>>> take? Do
> >>>>>> I replace the alternator at this
> point (find a way to swap the pulleys
> >>>>>> or
> >>>>>> get a replacement one with the
> correct pulley)?
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> Thanks in advance!
> >>>>>>
> >>>>>> Gregg
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> 91 Westy (Blueberry)
> >>>>>>
> >>>> --
> >>>> roger w
> >>>>   From Proverbs:
> >>>> Under three things the earth trembles,
> under four it cannot bear up: a
> >>>> servant who becomes king ...
> >>>>
> ----------------------------------------------------------
> >>>> Explore printed work at: http://www.prliving.ca/
> >>>> View the growing list of video work at:
> >>>> http://www.youtube.com/user/LastonLastof#g/u
> >>>>
> >>>> http://www.prpeak.com/articles/2010/11/29/multimedia/video/doc4c62e5f80d228504902172.txt
> >
>