Car is overcharging. Please help!!

-
Moparboyz01

Moparboyz01

Well-Known Member
Joined
Mar 20, 2009
Messages
62
Reaction score
1
Location
Blytheville,AR
My car is overcharging its reading 16 volts at idle and 18 when i give it some throttle. I have a 2 wire alternator and it looks fairly new i got it from one of my buddies because we thought minds was bad. Voltage regulator is new also i have tried to check grounds but i cant see anywhere that may be grounding out or not grounded at all so it is really frustrating me. When i first start car and take off car is driving fine but after a few seconds or minutes when i come to stop i hear a popping noise coming from exhaust and when i pull off it breaks up real bad. So i trying to distinguish if im getting to much gas the reason why it does that or is it a fire problem im using an electric fuel pump and regulator. I also have a brown lookin wire coming from starter relay that i dont have a clue to where it goes due to car had no motor or trans in it when i bought it. On the voltage regulator does both sides need to be grounded cause i only have one side that has a screw in it due to the place that i could put it on the firewall where the old style regulator was or do i need to move it. Can someone please help me fix this or these problems because they have me stomped. Thanks alot.
 
by a 2 wire alternator, you mean you have one large wire and one small one? If that is the case, it could very well be a bad ground on the regulator. On the older ones with one small wire going from the alt to the reg, the reg needs a real good ground because that is how it measures the voltage and knows how much current/voltage to allow through. If you have a bad ground there, it will overcharge.

Also, make sure you have a good ground from the engine to the frame/body.
 
My first thought was to stand back from this one . I dont know about electric fuel pumps and who knows what else. Then I got to thinking... That brown wire on the starter relay you mentioned is supposed to go to the neutral safety switch on automatic trans. The relay shouldn'yt work without it. Is it possible that your starter is running contiuously ? That would explain the high voltage.
the solid state regulator does need to be grounded well , even if done with only one screw. Scratch away paint or whatever to provide a good chassis ground.
 
I had some overcharge issues myself which caused my battery to boil over...I ended up buying a new alternator because the Diode was bad about a year ago (this was a BRAND NEW alternator). So, I took it back and they said it was a defect. But you also may replace your regulator. I recently had another overcharge issue with my duster and was thinking OH GOSH ANOTHER alternator....but I decided to change the regulator first, which didn't help. Then I got to looking and the plug that connects to the regulator which is the female end I think it was?, Was coming apar, which is a connection issue. So you may check that. Fixing that plug solved the WHOLE issue. I was charging at 18 volts when driving around 2200RPM and 16 volts at idle

Hopefully this may help?
 
I am still overcharging i have put on brand new alternator and voltage regulator i have changed out the plug to regulator and have moved regulator from firewall to fender and grounded it pretty well. So what else could still be causing this problem is it in wiring or im i missing a ground somewhere keeps blowing headlights. When cars is at idle needle is in middle and jumping and when i drive it goes past the C for charge and when i turn car off sometimes it stays up there but if i tap on gauge it will start to fall to middle. When it is at middle and i turn igniton key to on position it will go toward dead side until i start car. So im wondering could it be the gauge or something i hope someone can please help me again or tell me what else i may need to do. Thanks alot guys.
 
My buddy Brock has the same exact problem. We tried two alternators and they both do the same thing. One has one field wire and one has two field wires....they both tested good.

He has blown up/melted two regulators.

He had no problems before he painted his engine bay.

I have not been able to get back to him to help him but I was going to look at grounds at the firewall and from the block to the firewall.

Would running a ground from the battery to the regulator help? That was my next option if we couldn't get a good ground on the firewall.

I'm in the same over charging boat.....need help.

Mop
 
Moparboyz01 said:
I am still overcharging i have put on brand new alternator and voltage regulator i have changed out the plug to regulator and have moved regulator from firewall to fender and grounded it pretty well. So what else could still be causing this problem is it in wiring or im i missing a ground somewhere keeps blowing headlights. When cars is at idle needle is in middle and jumping and when i drive it goes past the C for charge and when i turn car off sometimes it stays up there but if i tap on gauge it will start to fall to middle. When it is at middle and i turn igniton key to on position it will go toward dead side until i start car. So im wondering could it be the gauge or something i hope someone can please help me again or tell me what else i may need to do. Thanks alot guys.
Click to expand...

Tapping on the lens is not good. It will break it away from the plastic bezel but should have no effect on the gauges. Heres a thought though... The armature in the amp gauge is magnetic. How the flakes of debrie find there way in there is beyond me but they do. I dont know if a short across there will cause overcharge either.
I have to suggest you disconnect the neg battery cable then remove the 2 wires from the amp gauge and bolt them together tightly and tape them good. This will rule out the amp gauge or proove it the fault.
 
We did that to our project....he put in an 65 amp alt so we bypassed the ammeter....just tied the two wires together and taped them up.
 
I would suggest you install a voltage guage and see what's really going on. To bypass the Amp guage correctly you need to use a crimp butt connector and solder. Then use shrink tubing to insulate the wires. All of your amps flow through that connection for the whole car. It also goes through the firewall connector which is another source of "Bad" connection. There are several articles about this by-pass which I would encourage you to at least read.

John B.
 
Yes I agree...The connection at the block on the firewall is crap. Also you are right about soldering and taping/shrink wrap the connection. We did that.

We are using a fluke meter to check the voltage when running and have a voltmeter gauge in the car as well.

I guess we will chase the grounds......I believe that is our issue.
 
There's two wires going to the regulator. One runs to the field on the Alt and the other is a wire that senses true voltage and should have 12V+ with the key on. If that wire does not have 12V, the regulator will think that the alt is not charging and allow current from the field wire to ground through the regulator body causing an overcharging situation.
 
OK that's like the ones I have for 67, 68 and 69 cudas...three separate ones.

I will keep on what I have traced....It has to be the grounds...I just haven't seen the car since last June and I wanted to be refreshed. I get to look at it in 2 weeks....belongs to a friend, who needs a helping hand as he likes to drive, but not work on them so much.

Thanks again....sorry I hijacked the thread...:stop:


Mop
 
No problem moparman since yall are haveing same problem maybe we can figure this thing out. Where does the ground from firewall to block connects at because i tried to trace down my grounds and i dont see that ground anywhere hopefully thats my problem so can someone tell me where it goes. Thanks
 
Its normally on the back of the block and attaches to the firewall to the right of the blower motor.....at least that's what I remember.

On my cuda I ran a ground wire from the battery to the frame then all around the car and tapped off it for different loads. I also bonded it to a starter bolt and to the transmission, bumper bracket and body.

I didn't want to rely on the ground strap and I had slicked off my firewall.

I will keep you posted on our progress when I get back to it in 2 weeks.

Good luck to you.

Mop
 
I opened this thread to check up on the issue...but my posts are gone?!?!?
Then I realized that this is the wrong thread... DoH! :lol:

Some good info on overcharging on this thread. dang near the same title... :)
http://www.forabodiesonly.com/mopar/showthread.php?t=90975
Troubleshooting steps are listed in post 12


I try to break the issue into simple pieces.
We know that the regulator isn't doing it's job, but why?

Ramcharger is right on, if the regulator doesn't "see" the correct voltage it can't regulate the alt correctly.
2 causes for the regulator not getting an accurate voltage reading.
Bad ground - regulator has noting to reference the +v signal to.
Poor signal input - too much resistance in the feed wire (ign switch, ign switch connector, bulk head connector, ammeter, dash solder joint, etc )
 
OK so we spent 4 hours on it Sunday and got the problem solved.

Here's a list of items we dealt with and how we corrected them.

1. Fuseable link was corroded and frayed at point where it entered the bulkhead connector. That slot on the connector was melted from the heat so it was useless. We used a spare slot in the connector and drilled a hole through it and the on on the firewall mounted part of the connector. Ran our new #8 wire from the relay through them and left enough slack so that the connector can be pulled off and away for maintenance. About 8-12" extra will do.

2. Sanded the firewall to bare steel where the ground strap attaches to the firewall. Clean both ends of ground strap.

3. Same as above where the voltage regulator attaches. Replaced bad wire from it to the ballast resistor.

4. Ran new #8 from our new alternator to the battery stud on the starter.

5. Cut the old alternator black wire back to the bulkhead and taped off

6. Cut loose ammeter inside and soldered wires back together bypassing the gauge. Installed Voltmeter gauge.

So we fired it up and voila......voltage at battery 14+....held at low RPM and at higher RPM. We were using one of my old VR's so we were concerned that it may not hold up but it has so far and its working great.

Hope this and the info listed in the other thread helps.....it helped us.

Mop
 
I had the same problem it was the voltage reg. on the firewall.It was not grounded because of paint made my alt. go bad. All of it went bad.I replace both of them one by one to find out the problem.When the reg. cant find a ground it shorted all of it,so i grounded the paint of the firewall were it bolts to and that was that. Something so small cause all that problem.I thought i put my two cent in anyway.
 
You must log in or register to reply here.
-

Back
Top