Archive for October, 2017

Vanagon – alternator voltage regulator re-brushing

During the summer, on a camping trip, the alternator failed. The brushes on the voltage reg finally wore out. I had a spare (used) voltage reg on board and the swap got us going again.

The failed regulator was an adjustable unit I bought way back in the early noughts. It got swapped over from my old 82 westy to the Syncro in 2011. It had been working perfectly all this time and I really liked the ability to up the voltage output a little to overcome any voltage losses in the wiring up to the battery and also to give my batteries a good charge.

I think the reg cost around 35 bucks back then, haven’t checked the prices these days. Might not seem cost effective to repair it, but I wanted to. Hey why not? What’s the point of other folk posting how to do it…

Local automotive electrics outfit, Brian Roberts, sold me a pair of brushes for 8 bucks.  Just $8, a little solder, flux, and time, and the reg was fixed.  I wasn’t very good at documenting the steps but here we go.

The new brushes look like this, carbon-like with a braided copper pigtail. The spring is the old one, no problem re-using.


Old brush…


To get the old brushes out, well originally, under the solder, the metal is formed into a tube which is crimped onto the pigtail, soldered, and trimmed.


I found that merely melting the solder didn’t release the pinched pigtail. So I drilled it out. That meant when I inserted the new brush and pigtail I had to hold the braided pigtail…


Pigtail with spring fed up into the brush holder on the reg, haemostat holding pigtail so brush projects fully but doesn’t come out.  Then, flux (rosin) and a good strong iron.


Was hoping for a better blob, but it’s ok.

And the iron? This old Weller, it’s a champ with this sort of thing.


 Same thing with other brush. Then trim the excess copper


So that’s all good. Hey just as an aside, clean up shiny, all the contacts on the reg and also on the alternator body.

Acesss to the lower machine screw holding the reg to the alternator is fussy in the stock wbx. An intake runner impedes screwdriver. 


An offset screwdriver does the job, albeit slowly. But beware, if you didn’t disconnect the battery then you can hit the hot stud on the alternator with the driver. The angry pixies make you jump. Foiled a second attack with heat shrink on the driver. But the pixies managed to nibble one end, see?


Oh, btw, adjustment of the reg is done via little screw.


Dialed mine up to 14.65 V at alternator. But I’ve noticed that the voltage will drop maybe half a volt or so when the alternator heats up. Btw, the multimeter is pretty good for $15, banggood. Auto ranging, back light, big display, AA batteries rather than 9V. Still have the protective film on display, it’s not a thing with me, just forgot.

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