Alternators

[V8 Sam]

Hello chaps.

My alternator has decided to fry the battery due to pretty Dodgy wiring in the back of it.

I'm looking at replacing it with a Lucas type one (much cheaper and easier to obtain in the UK)

They also have a built in voltage regulator.

My question is, should i remove the voltage regulator thats already in the wiring or just leave it in place? Not sure if a second one in line will mess with the voltage that's already been regulated coming out the alt. Or if it will stay the same

Thanks!



Small block 70 dart.

 

[Hellrats]

Removed it. It will not be needed and you do not want two voltage regulators in the system.

 

[Mattax]

Not sure what you mean by "wiring in the back of it."
There's either just one connector or two connectors, plus the output stud.

A short on the output will melt the fusible link.
A non-regulated output can boil the battery acid out. That's a regulator issue.

Converting to a internally regulator will need some wiring work. Otherwise the field connection may backfeed the ignition and the engine will keep running even with the key off.

 

[Hellrats]

All he needs is battery B+ at the post and one wire from "key on" to power up the regulator inside the alternator.

 

[toolmanmike]

Overcharging is usually a bad regulator, bad grounds, or corroded electrical terminals in the charging system. You may still have the issue with the new alternator.

 

[67Dart273]

"Your alternator" is not what is causing the overcharging except in rare instances. Might be a grounded brush if it's an isolated field, might be a short to ground in the rotor. That would be rare

MUCH more likely is (in no particular order)

1....Poor ground condition between REGULATOR and BATTERY
2....Voltage drop between REGULATOR and BATTERY in the harness/ bulkhead connector/ ignition switch/ connectors
3....Fairly rare is a defective regulator
4...Sometime a defective battery will cause this.

 

[V8 Sam]

sorry guys i should of explaind a little bit better.

The car currently has a lucas type alternator set up on it. LRA607 to be precise.

how ever its a proper bodge job. as ill show you in the pics below.

the red wire is the main wire that runs to the alt, that was sitting on the bodged bridge in the alternator in order to contact both terminals. and everyting else has been spliced into that cable. starter dash etc...

now i want to get keep the alt set up as they are a lot easier to obtain and much cheaper. plus i belive they are internally regulated. i also want to completely rewire it properly with fresh wires/connectors.(not fussed about it not being original, would much rather drive it then have the correct date coded wheel nuts etc)

now im not entirely sure if there even was a voltage regulator already inline or not as i haven't got around to checking just yet, so that was my main question, if i do find one, shall i remove it. next question would be where abouts would one normally be?

the car has run fine untill a few years ago when i last drove it, as i parked it up you could hear the battery hissing away from now what im assuming is this awful bodge wiring job hasnt helped.

hope that clears up a little where i am with it.

 

[67Dart273]

Again not familiar with this and not enough info to become so. If this has a separate "sensing" and or exciter wire, the rules as to overcharge due to grounding and harness drop still apply

If this is a "one wire" you MUST upgrade the charge wire as a "one wire" setup must have an oversized charge wire. This is because the voltage sensing in a "one wire" setup is through the one----wire. So drop in the wire will cause an UNDER voltage system condition, as the alternator is sensing right at the alternator

 

[Ottmundr]

Hello chaps.

My alternator has decided to fry the battery due to pretty Dodgy wiring in the back of it.

I'm looking at replacing it with a Lucas type one (much cheaper and easier to obtain in the UK)

They also have a built in voltage regulator.

My question is, should i remove the voltage regulator thats already in the wiring or just leave it in place? Not sure if a second one in line will mess with the voltage that's already been regulated coming out the alt. Or if it will stay the same

Thanks!



Small block 70 dart.

That's going to go over well...

 

[Mattax]

The car

now im not entirely sure if there even was a voltage regulator already inline or not as i haven't got around to checking just yet, so that was my main question, if i do find one, shall i remove it. next question would be where abouts would one normally be?

In reverse order, its probably on the firewall near the ballast resistor.
The illustration here shows a B-body. The 1970 Alternator & Regulator (Session 269) from the Master Technician's Service Conference
Post a couple photos of the firewall, especially if its a RHD model since that's a rarity here.

i belive they are internally regulated

I suspect you can get that info quicker than we can. We have to play games with the search engines to get them to prioritize stuff on your side of the pond.
The transistor on the outside of the alternator is probably a part of the internal regulator.

the red wire is the main wire that runs to the alt, that was sitting on the bodged bridge in the alternator in order to contact both terminals. and everyting else has been spliced into that cable. starter dash etc...

You can post some more pictures, and my suggestion is to draw out the circuits you find.
There's a number of ways this could have been wired into the original circuitry.

I see three spade tips on the back of your generator.
B probably stands for Battery. That would be the power output.
D I don't know. Often there is a sensing connection and a field wire.

Post some photos of the splice connections, and the bulkhead connector.
On a stock '70 Dart, there are two power feeds for running the car and all accessories.
One is a heavy wire from the alternator output through the firewall to the main splice.
The other comes from the battery. Carrying that power when needed is a heavy wire from the starter relay to the firewall with a fusible link in it. Then it too goes on to the main splice.

 

[67Dart273]

I've run into this before, a S American or Mexican car. They evidently came with Bosch alternators and are different than US cars. Yep, without further photos (like of the engine bay) difficult to tell what's what

 

[skykeith]

It looks like you need to repair the butchered up wiring on your car before you replace the alternator. Your alternator has the two B+ terminals same as some Ford alternators did. There is supposed to be two wires, usually in parallel going to those terminals. Someone has tried to run one wire off both terminals with a horrendously bad hack job.
D+ is the European marking for the field positive wire or power for an internal regulator, sometimes coming from a warning light.
You need to find someone to help you with repairing the wiring. A Lucas LRA607 will do a good job if wired properly.

 

[V8 Sam]

I've run into this before, a S American or Mexican car. They evidently came with Bosch alternators and are different than US cars. Yep, without further photos (like of the engine bay) difficult to tell what's what

Well now, it's funny you should say that, the car is Mexican.

Has a few other ford parts on it as well including a ford toploader 4 speed box (which was a nice little bonus when I bought it, very strong box!)

Came from factory with it too, something to do with keeping a percentage of the parts made for the car in Mexico or something.

I wonder if this Lucas type set up is from factory then...

I didn't mention it was a Mexican as I didn't think this would matter.

Either way you're all correct the wiring needs to be complete rendone, when I get a chance I'm going to pull all the wires out from battery to the key to the stater to the alt and re do a simple charging/starting circuit thats is not splcied into anything, I also have a proper 3 pin plug connector for a Lucas alternator so should be a lot happier.

Any of you guys run a battery light onto the dash? I have the square Speedo type wooden dash in mine and not the sweeping one.

Only dash lights are brake and oil.

 

[Mattax]

Well now, it's funny you should say that, the car is Mexican.

Has a few other ford parts on it as well including a ford toploader 4 speed box (which was a nice little bonus when I bought it, very strong box!)

Came from factory with it too, something to do with keeping a percentage of the parts made for the car in Mexico or something.

I wonder if this Lucas type set up is from factory then...

I didn't mention it was a Mexican as I didn't think this would matter.

Either way you're all correct the wiring needs to be complete rendone, when I get a chance I'm going to pull all the wires out from battery to the key to the stater to the alt and re do a simple charging/starting circuit thats is not splcied into anything, I also have a proper 3 pin plug connector for a Lucas alternator so should be a lot happier.

Any of you guys run a battery light onto the dash? I have the square Speedo type wooden dash in mine and not the sweeping one.

Only dash lights are brake and oil.

Actually I wouldn't replace anything until you understand the wiring scheme. The schemes Chrysler and other used at the time were generally very simple, but did use splices.
More later.
Mexican & SA cars are generally different, as are Australian Valiants, and to lesser degree as are US/Canada export builds for RHD.
Most Chrysler products of the era will have gages for charging, coolant temperature, and fuel level; a warning light for oil pressure, and the brake warning light.
If that's what your car has, the only one of possible interest a the moment will be the one that shows charging or discharging of the battery.
Power for to the instrument lights, the other gages and lamps is a whole other kettle of fish.
I'd stay focused on the power feeds and voltage regulation circuit.

The scheme for powering the alternator field is "ignition fed". This means the power for the field circuit is tapped off the ignition circuit. When the key is in Run position, power is available in the ignition circuit.

Up through '69, Chrysler used field positive switching for regulation. In '70 they used field negative switching. All that means is the regulator switched the earth connection on and off instead of the positive connection.

Below illustration shows the basic power feed circuit.

Whether power comes from the alternator or the it comes from the battery, the big welded splice distributes power for everything but the starter.
There are also other splices that act as distribution points. The accessory circuit has an important one. "Accessories" covers just about everything other than running the engine.



When the engine is running, power to the field comes from the ignition circuit.
This shows the current flow to the field with a positive switching regulator.

The earth switching regulator arrangement scheme is similar, except that the field negative brush has a wire connection to the regulator.