Battery emitting sulphur steam / voltage query

[oldpilgrim]

Sounds like the alternator is putting out too much juice for any old/new voltage regulator to handle.

 

[lpakiz]

If, and only if, you have an external regulator and suspect wiring, it may be that a wire that is used to excite the alternator has come into contact with a full system voltage wire. In which case, the regulator might be sending the proper signal to the alternator, but the faulty wiring is adding more (full system) voltage.
The advise to change to a one-wire unit is very likely to correct this problem permanently

 

[drizler]

Here's the simple and cheap solution. First off an alternator or starter should las a lifetime. They are easy relatively cheap and lend themselves to rebuilding. All the wear parts just pop right out.
Yank that unit and take it into a starter / alternator shop. Aka, DC motor shop. Tell him what it's doing and hav him fix it. He's got the test gear to do it right.
Secondly avoid buying big box store rebuilt units. They don't replace all the wear items unless worn out so chances are good they will give you one with something ready to go bad down the road. The local shop will do it right and should cost you half of that. Ew rebuilt from a store. The same goes for car starters and alternators as well.