[T3] Generator related questions

[Jim Adney]

Welcome to the list, Paul. We've emailed each other, but I don't 
think you've posted here before.

On 20 Jan 2011 at 20:24, Paul P wrote:

> Background ;  I´ve had an intermittent generator light coming on/off
> over the last three years of Type3 ownership - it used to come on
> sometimes (winter more often I think) and then go off after a minute or
> so. This pattern could disappear for months.  However, lately the
> light comes on at start-off and stays on - it needs a press on the top
> brush to put it off for the duration of a drive (this action decreases
> the idle speed by about 60 rpm) ;battery will then get its 14.1V at
> med/high speed. So I decided to physically examine the brushes etc (as
> a first step) .  

It is normal for the rpm to decrease once the generator is working, 
just because of the load it then applies to the engine.

Some questions ; 

> 1.  I´ve read that the T3 generator brushes** had notch sloping
> different direction than T1 ones ?? - if so, are these still
> available?? Haven't seen them on any of the sites.  Mine seem to be the
> normal beetle ones- notch, at the top, sloping away and down as you
> look at the brush with the wire side towards you. I´m going to try new
> ones to see if it improves the situation- although both the current
> Bosch ones had worn by 5 mm- not a huge amount since they were still a
> bit above the holder.    (** the original Bosch number on the 1970
> Bosch service list was 2 107 014 016,  to be replaced by 1 107 016 and
> maybe replaced again?! - don't know?the VW numbers) 

The number I show for the brushes is 1 107 014 146 (or 11 004.) I've 
kept one set of these still sealed in the original bag so I can check 
this exact detail. The notch on these slopes AWAY from the pigtail 
(high side toward the pigtail.) If you have the other version, you 
can easily slope it the opposite way with a square file or a pocket 
knife; the carbon is very soft.

> 2.  There is what appears to be a lot of dirt and fibrous type `junk
> around one side of the cooling aperture on the underside of the
> generator (as in Haynes manual p 149 photo12.10a) , but it looks like
> some form of insulation !  Should I remove all this stuff ?? There is
> some bright exposed copper strands (running length of generator),
> where I picked off some- its not the armature ? with the?segments. 

You're looking at one edge of one of the field windings. It's a good 
idea to brush away the dirt, but leave the wound paper insulation 
intact as much as you can.

> 3. I noticed that the belt ( which seemed to have the right tension)
> had a significant split of a few mm at one point - so I am going to
> replace it. I have a >  recommended Bosch replacement part, 8713, 
> with is 10 x 10000 mm and toothed - maybe the original Continental is
> prob slightly better at 9.5 x 10000 and V shape,  but can I presume
> the Bosch will be ok for a few years at least (low mileage) ??  

The correct size is 9.5 x 1000 La. I don't know what the La stands 
for but 10 by 1000 will stand a little higher in the groove, so 
you'll need to readjust the shim washers in the generator pulley. I 
know some Mercedes used the 9.5 x 1000 La belts, too, so that might 
help you find an exact replacement. The toothed belts work fine.  

-- 
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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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