People usually have gotten the alt. replaced over the years on these; mine still has the old external regulator (which is probably fine), but the alt. has internal regulator. I'm not saying this as an endorsement of the idea, just that it has usually been done.

I just dealt with this on the weekend. Please don't replace your alternator. You probably only need brushes. A reputable starter/alternator shop can do the job and confirm correct operation on their bench. You just need to bring them the device. This was the route I went and it was inexpensive albeit gruntish.

I could have just ordered a new VR/brush set; this is a trivially easy job.

You don't GET a new alternator when you replace. You get one that is functionally exactly the same as your old one, used, with its problem repaired, (which you should have done anyway) with a shiny appearance. Dirt does not affect alternators, which is an external device.

Some business. They get your perfectly fine old one for peanuts, fix it for next to nothing to sell to the next guy, gouge you on a used replacement that cost them nothing to "rebuild", and you are okay with this because they have the "expertise".

The "alternator" is a simple, robust device, _somewhat_ like your "car". If "car" has trouble, you think long and hard about replacing the whole thing, and you do your homework. Too many people turn off their brain and open their wallet when it comes to automotive electrical systems.

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__Stef -- 81 DL wagon B21A SU carb M46 314000km