Alternator spewing out 50v What to do?

[Jedidiahwiebe]

Hey! Just noticed that my Alternator is spewing out 20-50v. It's fairly new so I'd rather not replace the whole thing. Can I just put a new (or used perhaps) regulator on it?

I've got a battery isolator fortunately which has blocked (by sacrificing itself) any of this excess voltage from damaging important things in my system such as the battery.

Any thoughts? How do I identify the regulator and is it possible to fix?

Thanks everyone!
Jed

[Growlerbearnz]

Is the Sense wire ("S" terminal on alternator, usually in the same plug as the L (lamp) terminal) still connected to the main battery? If the sense wire is disconnected, or poorly connected, (or connected through a battery isolator maybe?), the alternator thinks the battery is dead and bumps up the voltage to try and compensate.

On the wiring diagram I have the sense wire goes through one of the fusible links. It's the thin White/Red stripe wire, the lamp wire is Blue. YMMV.

[Jedidiahwiebe]

I disconnected the lead that I had going to the isolator (two thick white wires with red stripe) and connected it onto the battery and got normal voltages! Seems to be working for now! Thank you so much! I hope I can find this 'sense' wire and ensure that it is properly connected. Thanks again eh?

Btw how can I tell which is the S and the L terminal on the alternator? I only see one terminal for some reason. Maybe I'm forgetting. Just changed the alt a few months ago. Ran fine til last week.

[Growlerbearnz]

There's the big terminal which goes to the battery via the two white/red cables, but there's also a plastic plug with a couple of regular sized wires in. Usually the back of the alternator is marked S and L beside that plug, but if yours isn't marked, the S wire should be the same colour as the two big cables- white/red.

[Jedidiahwiebe]

Cool thanks. Yea there's been a mouse chewing things up in the van. Probably should check the continuity of that wire!