Electrical charging isssue...

Tried to start the jeep tonight, and the battery only had a minimul charge and tried a couple of times to start before dying. I push started to get home, but as I was driving the second or third mile, the lights seemed to get dim. The amp meter I have on my dash was initially reading slightly below zero at about a -1 or so, and seemed to move to 0 toward the end of the drive.

Tomorrow I will go and test the battery to make sure that I am near 12v before starting, and then hopefully closer to 14-15 when running. I think it is either the alternator or voltage regulator.

Is the cheapest voltage regulator going to be about $60 as kaiserwillys suggests, or is their a swap that is cheaper?

If it going to be $60, I would rather switch it out for a new alternator that is $80 or $90.

What part number would be a moderate alternator upgrade? the delco 10si? where would I find the best price?



Ben

 

What do you have in there now? It's possible that you have a loose/corroded connection, regulator excitor circuit fuse blown, many possibilities depending on what you are running and how it's wired. Need more info.

 

A Delco 10 SI 62 amp can be had at Pep Boys for $29 exchange, Just ask for an alternator for a 76 Chev PU with v8 auto and air. The 1 wire or 2 wire hookup is simple and been covered many times in the forum, With the 10 SI you have the alt and regulator in 1 package and it is easy to upgrade to 108 amp if needed.

 

Thanks for the input there...

Seems that I was under some misconceptions about what I was running...After looking into it today, it seems that I am running a generator and voltage regulator. Couldn't get any number or brands off of either, but I took pictures of them opened up and will post tonight. What I found most interesting, is that the voltage at the battery when running was only about 12.05 and it fluctuated wildy down to things like .06 being the lowest I saw, but frequently kind of bouncing between about 6 9 and 12. I tightened the generator to belt to make sure that it wasn't slipping, and things did seem to improve to a general 12.9 ish but still bounded around a good bit.

Will post pictures tonight, to me it kind of seems like it is the voltage regulator even though that looks like it is almost new and the generator looks way older.

Ben

 

Might not be it, but one thing to check is bypass the ampmeter. I had one years ago that went 'bad' and wouldn't allow my battery to charge fully anymore.

Not a 'sure thing', but very easy to bypass and check.

 

Checked voltage coming off of the generator and got a consistent .26 v reading. Went ahead and ordered a new voltage regulator coming in tomorrow.

 

That doesn't mean your voltage reg is bad. You have to full field the gen while running to make sure the gen is putting out or not. Could be brushes are worn out. Or carbon jammed and wont make contact with armature.

 

Replaced the voltage regulator and nothing changed...

If I test the voltage from the generator with a voltage meter with the red on the armature and the black grounded, what should it read?

If I connect the field terminal from the generator to ground, what should the voltage read at the battery? at the armature?

What clues should I be looking for to determine if the generator is not funcitoning?

 

I did not change or replace the generator, although I did take it appart and look at it. Do I need to polarize the generetor in this case? I read the article on vernco, but am not clear if replacing the voltage regulator would require this polarization?

Thanks for the input in this...

Ben

 

I am getting confusing information...The vernco.com article mentions running a quick charge from the battery terminal on the voltage regulator to the arm terminal on the voltage regulator, only if I know that the generator is externally grounded. This is an assumption, but not definite. It says that I can double check this but measuring the ohms between the field and the armature on the generator, and how they change when i remove or create a space between either of the bushings. Now correct me if I am wrong on any of the above...

Does this ground the generator, when I flash the external regulator?

Other articles mention that it can be harmful if I have run the jeep without polarizing the generator(by apparently flashing the voltage regulator...)

While it is irritating for my jeep to stop running even for an afternoon, it always leads to this delightful insight into how it runs. I am usually happy learning about all of this as long as it does not lead to costly parts or extended delays in fixing the issue.

Thanks
Ben

 

I fought with my voltage regulator for a few weeks when I rewired my jeep. Couldn't figure it out and I'm an electrician! I still went wheeling, just brought 4 batteries with me.

I went to Autozone and bought a 10 SI alternator internally regulated from a 71 firebird. My jeep was fixed and running great a couple hours later. Its a much simpler set up and more reliable in my opinion. I've been stuck in a river twice since then. My Alternators cooked a few days later and covered under the lifetime warranty both times. Its a 10 minute swap out in the parking lot, no receipt needed. For 34 bucks you can't beat it. Save yourself the headaches.

 

What ever you do -- Do Not flash to v-regulator.. You will destroy it. You flash the generator only and that is with regulator disconnected.. You may have gotten the right regulator for your year/model jeep but you may not have the correct gen. Since you did have the system operating very recently, it's not likely you need to polarize the gen but more likely you need to open gen and clean and check internals. HTH

 

I did open the generator and checked everything that I could see. Seemed clean and everything in reasonably good shape. The voltage regulator needed to be polarized per the instuctions that came with it, and I did that. I had the battery checked and it was bad, I replaced it, but it does not change that I am not getting a charge, and the reading when running still bounces around to all kinds of numbers like 12 6 0 3 9 etc. on the voltage of the battery. When jumper cables hooked up from my exterra, I get a constant 14. The voltage regulator is new, the battery is new, all connections are in good shape, the only thing left is the generator. It is running now, but I think just because I haven't run it long enough for the battery to lose it's charge. When driving the ammeter reads about -1 with the headlights on, and pretty much dead zero with them off. The amp light on my speedometer is on, which happened about a week ago. I believe that I will just run it like it is for the next couple of days until I order the kit from willysworks and a new alternator...

Ben

 

Go the SI route. Figuring out the generator stuff will make you bald!

 

What if he's already bald?

 

Found this old post and was able to replace my Motorola alternator with this one. Thanks!!