Alternator belt slipping?

[cutlass]

I've installed a WAI 120a alternator. At idle it charges well.

But as I increase revs it's amps drop to zero!

It's pulley is significantly narrower than the previous one. The drive belt is new but I've noticed it has quickly worn in the edges.

My thoughts are the pulley is too narrow and the belt is slipping at high revs.

Or is there something else I'm missing?

[sctpc]

Originally Posted by cutlass

It's pulley is significantly narrower than the previous one. The drive belt is new but I've noticed it has quickly worn in the edges.

My thoughts are the pulley is too narrow and the belt is slipping at high revs.

Or is there something else I'm missing?

Assuming you have it tight

You have the wrong drive belt, The belt is just working on the edges off the pulley, your belt must fit inside, when it rubs away all the edge it will be lose so will slip so id get a smaller width the pulley to work properly.
The other way is to change over your old pulley.