B+ B+ Alternator with pics

[Paul D]

Well I will probably get flamed for this but I bought a duralast alternator because I wanted quick so I could make it to a show / campout this weekend. Got everything installed and ready to go, then put the ground on the battery. Sparks and smoke started rolling and I pulled off the ground. The wire to the starter to the B+ B+ connection on the alternator was toast.

This leads to the question. I have two posts on the back of the alternator which are a B+ and a B+ B+. Everything I have read so far say to connect to the B+, but on the old alternator this wire was connected to the B+ B+ too. Their was an internal wire on the old alternator that connected to the B+ terminal so I assumed that it would be the same on the new alternator.

So which should it be the B+ or B+ B+?

I will also include that the old wire was taped up very good with some kind of funk electrical tape. It looks like someone had some issues with this wire before. This leads me to wonder if the wire just shorted on something.

[Paul D]

40 looks and no takers yet.

I am hoping to take a look at this again this afternoon. Hopefully I don't have to go to the trial an error method.

BTW it is a 74 with a type 4 engine. It appears to have once been wired for a dual battery.

Thanks in advance

[mygreenbus]

Not familiar with type 4's but I'd replace the funky taped wire in anycase. Then it will be eliminated as a problem on this and future problems (hopefully none)
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'72 Bus

[busdaddy]

Pretty confusing question you've written there Paul.
I've never seen anything other than B+, F, L and G on an alternator, this B+B+ post sounds odd, try the B+ to the battery and hope you didn't cook the new unit. Always replace funky taped up wires, they usually cause more problems than you are even aware of.

Pictures may help.
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[Paul D]

Thanks for the replies and here are the pictures.

First the old. B+B+ on the left and B+ on the right.
The B+ runs from the post to the wire in the center.

The new has two posts. Once again B+B+ on the left and B+ on the right. This picture didn't come out very clear, but you can pick out the B+B+ and B+.

I have some 10 gauge red wire that I was going to use to replace.
Do you think that is sufficient?

[Paul D]

I started looking at the old and new, and I am guessing that the black "doomijining" on the old alternator should be hooked up to the B+?

It has part 0 290 800 on it, does anybody know what that is?

[Paul D]

I feel like I am having a one person conversation here, but I hooked it up as the old alternator with the little "doomahicky" attached to the B+ and the starter to B++. I am getting about 12 on volt meter and the battery is low so I am charging it up right now. I will test again after I get a full charge.

New problem....the alternator light is always on when the engine is off. It goes right off when I start it up.

I checked #11 fuse and it looks fine, but I thought the light would go off when I pulled it.

Disconnected the wiring harness from the voltage regulator and the light is still on.

Any ideas please?

[1975 Kombi]

I have taken my Alts to a Alt rebuild guy to find the answers. He will test it and tell you what everything is.
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Brett

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[Wildthings]

There is no B+B+ post, they just stamped it so it can be read in two different orientations. Both of your B+ posts are the same, it doesn't matter which one you hook your B+ wire too, use whatever seems to line up the best.

[Paul D]

Thanks for clearing that up!

Now how about the alternator light being on with ignition being off. Did I fry something....should I start a new post?

[RZAR]

[old DKP driver]

The plate on the back is called the Rectifier that hold the diodes
It's very common for there to be 2 B+ terminals.

the little black "box" is the radio interference suppressor

And also on the back of the alternator housing are 2 little halfmoon rubber insulators to keep the B+ terminal from grounding out on the cover.also there should be a Gasket on the alternator body to cover and a rubber boot protecting the B+ connection.

Paul,your first picture of the alternator has those 2 rubber insulators at the top of your pic.

there should also be (2) fiber washers under the B+ posts that you can see have been removed.
is your harness in good shape? or do you have to make a new one for your plug and replace the 10 gauge wire to the starter
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V.W.owner since 1967