Loose alternator stud

[Set2sea]

I'm back to alternator not charging. Last season it was the fuse receptacle by the alternator - wire pulled out.  I replaced that last year, that  checks out fine. No problem starting , just not seeing volt meter going to around 14 like it would normally on a low battery. The only thing I found was the positive stud on the alternator is loose to the alternator. I was not able to hold the stud and tighten the nut, the loose stud and nut turned together. Has anyone seen this. Could this be my charging problem.

[prh77]

Probably your charging issue, but more importantly a potential safety issue. Take the alternator to your local automotive electric shop for repair.

[Stu Jackson]

I agree with Peyton.  This happened to me just last week!  The positive stud is installed with an isolator around it, which keeps the + stud from shorting across the case of the alternator.  Take it off and get it fixed, sparks ain't fun.

You should also determine the cause of the failure.  If the isolator melted, you may be taxing the alternator too much, which would require reprogramming your external regulator, if you have one, with either amp manager or small engine mode or both.

[Set2sea]

Thanks guys. Sounds like I will be pulling the alternator tonight. Stu when you said "taxing the alternator" a light went off. When I did the glow plug upgrade, I looked at the system and connected the 8 gage that goes to the solenoid to the pos alternator post instead of the starter because it was much easier to reach. As well, I thought, what's the difference when you have the connection from the pos of the starter right to the pos of the alternator? I have a good alternator shop close by, I think I will go have a conversation with him.

[Ron Hill]

Paul : "Taxing the alternator" means that the alternator is putting out too much current or Hi current for too long a time period - heating up the case and possibly melting that + stud insulator.

That's why it's an important feature of an external Voltage regulator to have a alternator case and battery temperature sensors.  That way if the alternator case or the battery starts to overheat the regulator cuts down the alternator output - automatically!!

A thought

[Set2sea]

I see, thanks Ron. The alternator is in the shop right now, I will speak with them about a temp switch. After taking the alternator case apart, we could see that the pos stud was separated internally, I think he said from the rectifier.

[Stu Jackson]

Paul, do you have an external regulator?  If so, which one?  If not, you won't be able to use a temperature sensor.

[Ron Hill]

Paul : The temperature "controller" is an integral part of the voltage regulator.  The sensor wire temp from the alternator case or battery/s is sent to the voltage regulator.  The regulator then sends a signal to the alternator to change the current output.  Clear as mud??

It's not an add on. You have to have an external regulator that has that capability.