However, the alternator only produces a tiny amount of juice.
Simple things first. Make sure all battery charging cable connections are clean and tight, including the ground cables.
Do you have the 12 volt (automotive) wiring schematic for your coach?
Where are you measuring the "tiny amount of juice"?
Try checking voltage output (engine running) at the alternator B (+) output terminal, AND at the battery isolator alternator post and start battery post, AND at the POS post on the start battery. If you can give us the readings from all 4 places, it will help to diagnose your problem.
It is possible for your alternator to work fine on a test machine, but then not work on your coach. When the alternator is connected to a diode based battery isolator instead of directly to the start battery, the charging output cable does not "see" battery voltage. Your alternator may require a small gauge "excite" wire which is HOT when the ignition switch is ON. If so, and if this wire is missing or broken, then the alternator will not put out juice. We need good clear closeup photos of the back side of your alternator, and of the I.D. label. We need to know the alternator brand and model, what the terminals look like, and how many wires are connected.
See the thread linked below for a somewhat clear explanation of a DUVAC alternator charging system.
What is DUVAC? (https://www.foreforums.com/index.php?topic=33250.0)
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 22, 2021, 12:32:11 am
In the morning, I will get the data for you.
the connections are clear and solid.
the battery reading looks to be at 12.2, the alternator was about 1.3. at idle.
I have the service manual, and a great parts store. I will get you all the readings sometime tomorrow, hopefully in the morning.
Title: Re: battery not charging 87' GrandVilla
Post by: Dakota Slim on January 22, 2021, 08:52:37 am
Battery voltage of 12.2 is not good...
Title: Re: battery not charging 87' GrandVilla
Post by: oldguy on January 22, 2021, 09:42:16 am
Do you mean 1.3 or 13
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 22, 2021, 04:30:49 pm
Yes, it read 1.3. Not 13.
Seems hubby is not so good with some things, so I will go back and double check all the readings. I work all day, so it might be hard to get them till Sunday morning...
Title: Re: battery not charging 87' GrandVilla
Post by: Protech Racing on January 22, 2021, 04:46:26 pm
Post a pic of the alternator wires. I had one break that is the field/ exciter wire. Mine ran to the fuel injector solenoid , about 8 inches.
Title: Re: battery not charging 87' GrandVilla
Post by: oldguy on January 22, 2021, 05:08:03 pm
Being 1.3 the alternator is not putting out so you need to find out why. First let us know what coach you have. Did this happen after you did all the work.
Title: Re: battery not charging 87' GrandVilla
Post by: wolfe10 on January 22, 2021, 06:45:25 pm
1.3 VDC is a COMPLETELY DEAD BATTERY.
Before troubleshooting, fully charge it and have it load tested.
THEN do the tests.
Title: Re: battery not charging 87' GrandVilla
Post by: red tractor on January 22, 2021, 08:48:51 pm
I think that this is a Oskosh rear engine gas which has a 460 Ford engine. They came with a Ford alternator with an external regulator.
Title: Re: battery not charging 87' GrandVilla
Post by: wolfe10 on January 22, 2021, 08:57:36 pm
Yup, we REALLY need to know what coach/chassis/engine you have to be able to give you sage advice.
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 22, 2021, 09:02:29 pm
1.3 VDC is what the OP was reading at the alternator - not the battery voltage. Battery was 12.2 VDC.
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 23, 2021, 12:34:31 am
Mine is an Oshkosh with a reap push gas Ford 460 ( and I rather like how she takes hills... :)
I will proceed with checking the excite wire ( which I had thought was the ground...) This will tell me about the juice going into the system.
From there, maybe the belt is not tensioned perfectly. I will only check the belt after I determine that there is enough excite juice. I do have a new volt regulator if I need it.
Title: Re: battery not charging 87' GrandVilla
Post by: Subsilked on January 23, 2021, 08:34:58 am
I think that this is a Oskosh rear engine gas which has a 460 Ford engine. They came with a Ford alternator with an external regulator.
Our front gas 454 86 GV had a FORD alternator with external regulator from factory. We had a failure on a TX trip and replaced with a new FORD alternator with ONE wire
Title: Re: battery not charging 87' GrandVilla
Post by: Olde English on January 23, 2021, 02:25:54 pm
I had a similar problem, turned out it was a $5 relay, runs from the alternator rear over to the bay wall under the bed.
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 27, 2021, 06:49:48 pm
Hello again!
Ok. So volt regulator has been replaced. We have 12 volts coming from the alternator
But not enough to be considered good.
What should I check next?
Title: Re: battery not charging 87' GrandVilla
Post by: Pierce & Gaylie Stewart on January 27, 2021, 07:32:18 pm
Our front gas 454 86 GV had a FORD alternator with external regulator from factory. We had a failure on a TX trip and replaced with a new FORD alternator with ONE wire
I had a Lucas alternator on my Perkins boat engine. It failed fairly quickly on our trip so when I came back to the States, I ordered 3 single wire alternators from JC Whitney. Easy to wire from the big alternator terminal to anywhere you want. They were only $16 back in the early '80s. Not that hard to find one that matches the pivot and mounting points.
Pierce
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 27, 2021, 07:46:19 pm
I had a Lucas alternator on my Perkins boat engine. It failed fairly quickly on our trip so when I came back to the States, I ordered 3 single wire alternators from JC Whitney. Easy to wire from the big alternator terminal to anywhere you want. They were only $16 back in the early '80s. Not that hard to find one that matches the pivot and mounting points.
Pierce
ok, sounds really attractive... but this would mean by passing the isolator? or pugging into the isolator and regaining the system from there? what size alternator, and how would it know if it was ovwecharging? what about the house battery?
Title: Re: battery not charging 87' GrandVilla
Post by: craneman on January 27, 2021, 07:55:39 pm
It wouldn't work with the isolator as the voltage has to be turned up .7 volts to allow for the voltage drop in the isolator. If you had bought a combiner instead of and isolator form Blue Sea it would work with an off the shelf alternator.
Title: Re: battery not charging 87' GrandVilla
Post by: Pierce & Gaylie Stewart on January 27, 2021, 08:05:09 pm
On our 7.3 diesel conversion on the old SOB, I just plugged the single wire into the isolator and it worked OK. You can pay a voltage penalty connecting an alternator straight to a solid state isolator. But there are a couple of ways around it. Read here: Tech Tips - Battery Isolators in Three Flavors - RV LIFE (https://rvlife.com/tech-tips-battery-isolators-in-three-flavors/)
If you have a DUVAC alternator, read here. How to Wire a Battery Isolator in a Camper | It Still Runs (https://itstillruns.com/wire-battery-isolator-camper-5436541.html)
Pierce
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 30, 2021, 10:50:44 am
Simple things first. Make sure all battery charging cable connections are clean and tight, including the ground cables.
Do you have the 12 volt (automotive) wiring schematic for your coach?
Where are you measuring the "tiny amount of juice"?
Try checking voltage output (engine running) at the alternator B (+) output terminal, AND at the battery isolator alternator post and start battery post, AND at the POS post on the start battery. If you can give us the readings from all 4 places, it will help to diagnose your problem.
It is possible for your alternator to work fine on a test machine, but then not work on your coach. When the alternator is connected to a diode based battery isolator instead of directly to the start battery, the charging output cable does not "see" battery voltage. Your alternator may require a small gauge "excite" wire which is HOT when the ignition switch is ON. If so, and if this wire is missing or broken, then the alternator will not put out juice. We need good clear closeup photos of the back side of your alternator, and of the I.D. label. We need to know the alternator brand and model, what the terminals look like, and how many wires are connected.
See the thread linked below for a somewhat clear explanation of a DUVAC alternator charging system.
What is DUVAC? (https://www.foreforums.com/index.php?topic=33250.0)
hi again,
After many days and learning so much, the following has been determined. the alternator will read the battery charge amount.
I changed the volt regulator and tried to excite by giving power directly to the s wire on the volt regulator with a small wire and a grounded jumper pack, and to no avail.
I got a new alternator. I installed a new isolator.
Do you have any final thoughts? I know there are fuselinks. Should I just replace the wire anyways and see? if so which one?
With all said and done, It appears the alternator is not getting the excite signal.
Title: Re: battery not charging 87' GrandVilla
Post by: Dakota Slim on January 30, 2021, 11:40:23 am
You seem to have thrown lots of parts at this problem. What are you using for a start battery and what is the current voltage? Are the battery terminals clean and the cables tight?
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 30, 2021, 11:48:40 am
I changed volt regulator and tried to excite by giving power directly to the s wire on the volt regulator with a small wire and a grounded jumper pack, to no avail.
I know there are fuselinks. Should I just replace the wire anyways and see? if so which one?
With all said and done, It appears the alternator is not getting the excite signal.
Try to use a logical approach to finding a solution.
In typical alternator terminology "S" does NOT indicate the "Excite" terminal. "I" (for Ignition) would commonly indicate the "Excite" connection. This marking may also hold true for voltage regulators, although I'm not sure cuz it's been decades since I last saw one. See diagram below for a generic diagram of alternator + external voltage regulator. Notice the switched ignition signal goes to the "I" terminal on the regulator.
If you believe the alternator is not getting the excite signal, try to determine why.
Try to search the alternator brand/model number online. There are "installation instructions" available online for almost every common alternator. If you have a separate voltage regulator, you also need the instructions for that device.
The reason you want to see the installation instructions is to identify the correct connection of wires to the alternator/regulator. Does the alternator (or the regulator) have a terminal dedicated to a EXCITE wire connection? If so, do you have a wire connected to that terminal?
If you DO have a EXCITE wire connected to the alternator/regulator, is that wire HOT when the ignition switch is turned to ON position?
IF the wire is HOT with ignition, then it is good. If not, you must either replace the wire or find the break and repair the wire.
Any length of wire, or fusible link, can be easily tested for continuity with a multimeter or even a simple 12 volt test light.
Title: Re: battery not charging 87' GrandVilla
Post by: red tractor on January 30, 2021, 07:50:02 pm
Look up for like a 84 Ford pickup with I think 100 amp alternator wiring and this should help sort this.
Title: Re: battery not charging 87' GrandVilla
Post by: Protech Racing on January 30, 2021, 09:51:18 pm
Often the Ford voltage regulator has to be grounded, and grounded to the engine as well as the battery . Any period correct service book for Ford will show the diog tree for the alternator and tell how to full field the alternator.
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 30, 2021, 11:09:59 pm
You seem to have thrown lots of parts at this problem. What are you using for a start battery and what is the current voltage? Are the battery terminals clean and the cables tight?
Admittedly, when I am coming across old and warn parts, I am replacing them indeed. Some actually needed it. the start battery is good, Kirkland brand and nearing the 4 year mark, I will replace this later on....
just for the info, I got a screaming deal on this baby. even if I put 8K into it ( which I plan to do) it will still be less then its worth. and yes, labor of love, and no frustration. I love the journey.
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 31, 2021, 12:27:52 am
Try to use a logical approach to finding a solution.
In typical alternator terminology "S" does NOT indicate the "Excite" terminal. "I" (for Ignition) would commonly indicate the "Excite" connection. This marking may also hold true for voltage regulators, although I'm not sure cuz it's been decades since I last saw one. See diagram below for a generic diagram of alternator + external voltage regulator. Notice the switched ignition signal goes to the "I" terminal on the regulator.
If you believe the alternator is not getting the excite signal, try to determine why.
Try to search the alternator brand/model number online. There are "installation instructions" available online for almost every common alternator. If you have a separate voltage regulator, you also need the instructions for that device.
The reason you want to see the installation instructions is to identify the correct connection of wires to the alternator/regulator. Does the alternator (or the regulator) have a terminal dedicated to a EXCITE wire connection? If so, do you have a wire connected to that terminal?
If you DO have a EXCITE wire connected to the alternator/regulator, is that wire HOT when the ignition switch is turned to ON position?
IF the wire is HOT with ignition, then it is good. If not, you must either replace the wire or find the break and repair the wire.
Any length of wire, or fusible link, can be easily tested for continuity with a multimeter or even a simple 12 volt test light.
.... ok. I have a picture here of the replacement I was given for the alternator. There does not seem to be an excitement wire, unless it is coming through the sense wire. ( can not attach a photo!)
there is a positive 4g wire, there is a negative 4G wire (ground) and then there is a combo plug for a FLO and a STR
I checked the voltregulator. the I prong is not hooked up, and I heard somewhere it was supposed to be unhooked. this would mean that the alternator I have should be internally excited from the belt spinning it.
Can anyone support this claim? this seems to be a carquest rebult alternator.
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 31, 2021, 08:38:18 am
.... ok. I have a picture here of the replacement I was given for the alternator. There does not seem to be an excitement wire, unless it is coming through the sense wire.
I checked the voltregulator. The I prong is not hooked up, and I heard somewhere it was supposed to be unhooked. This would mean that the alternator I have should be internally excited from the belt spinning it.
Can anyone support this claim? this seems to be a carquest rebult alternator.
1. The "Excite" and the "Sense" wires on an alternator can never be the same wire, because they have two distinct functions. If your alternator supports these functions, it will have two separate terminals for these wires.
2. The alternator you have may "Sense" the battery voltage through the large B (positive) charging cable. IF this is the case, and IF your alternator is connected to a diode based battery isolator, then the alternator might turn itself on, but it will not supply the optimum charging voltage to either battery bank. What is DUVAC? (https://www.foreforums.com/index.php?topic=33250.0) You said you have a new battery isolator. What is the brand and model number?
3. "I checked the voltage regulator. The "I" prong is not hooked up, and I heard somewhere it was supposed to be unhooked. This would mean that the alternator I have should be internally excited from the belt spinning it."
Some alternators are indeed internally (self) excited...some are not. Depending on what you "heard somewhere" to establish this fact is not the greatest idea. I again urge you to find a copy of the installation instructions for your alternator, either online or from the seller. If you are not Google search savvy, post the complete model number info (from the tag on the alternator) and we will try to find the installation sheet.
It is not a good idea to "experiment" with hooking up wires to alternators and regulators in a random fashion. Tends to let smoke out.
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 31, 2021, 12:07:05 pm
OK, based on your description of your alternator connections, I found the video linked below. I'm guessing your alternator looks similar to the one in the video? I personally learned a bunch from watching the video. For one thing, the generic diagram I posted in Reply #22 does not exactly match this setup (connection to "I" regulator terminal is different). Hope it helps you understand how your system works.
The video explains the meaning of the alternator combo plug connection for FLD and STR. FLD = Field. STR = Stator.
According to the video, the Field (FLD) wire is what energizes the alternator. When that connection on the alternator "sees" 12 volts, the alternator starts putting out charging voltage. This, then, functions as the "excite" connection on the alternator.
The voltage regulator has 4 terminals: "I" = Instrument (or Indicator) Used to power optional idiot light on dash. "A" = Battery Positive (should be HOT at all times) "S" = Stator (should be HOT only when ignition switch is ON) "F" = Field (goes to FLD connection on alternator)
The wire going to the FLD plug on the alternator comes from the "F" terminal on the voltage regulator.
The "S" terminal on the regulator is connected to a "HOT with ignition switch ON" voltage source. When this terminal "sees" 12 volts, it tells the regulator to send current down the wire to the FLD terminal on the alternator, which turns the alternator ON.
Armed with this info, you should be able to test the connections on your setup, and determine what is working and what is not.
https://www.youtube.com/watch?v=KjdaTypqj6o
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 31, 2021, 12:50:08 pm
OK, based on your description of your alternator connections, I found the video linked below. I'm guessing your alternator looks similar to the one in the video? I personally learned a bunch from watching the video. For one thing, the generic diagram I posted in Reply #22 does not exactly match this setup (connection to "I" regulator terminal is different). Hope it helps you understand how your system works.
The video explains the meaning of the alternator combo plug connection for FLD and STR. FLD = Field. STR = Stator.
The Field (FLD) wire is what energizes the alternator. When that connection on the alternator "sees" 12 volts, the alternator starts putting out charging voltage. This, then, functions as the "excite" connection on the alternator.
The voltage regulator has 4 terminals: "I" = Instrument (or Indicator) Used to power optional idiot light on dash. "A" = Battery Positive (should be HOT at all times) "S" = Stator (should be HOT only when ignition switch is ON) "F" = Field (goes to FLD connection on alternator)
The wire going to the FLD plug on the alternator comes from the "F" terminal on the voltage regulator.
The "S" terminal on the regulator is connected to a "HOT with ignition switch ON" voltage source. When this terminal "sees" 12 volts, it tells the regulator to send current down the wire to the FLD terminal on the alternator, which turns the alternator ON.
Armed with this info, you should be able to test the connections on your setup, and determine what is working and what is not.
https://www.youtube.com/watch?v=KjdaTypqj6o
Yes, this does give me all I need to know to follow the current system. Yes, It does look just like the alternators on hand.
The remaining two questions....
1. do I have an idiot charging light in the instrument panel somewhere? when all is said and done might be nice to hook up later.
2. Does this alternator have any issue with an isolator after it instead of being a direct connect to the battery?
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 31, 2021, 01:14:48 pm
1. do I have an idiot charging light in the instrument panel somewhere? when all is said and done might be nice to hook up later.
2. Does this alternator have any issue with an isolator after it instead of being a direct connect to the battery?
1. I don't know. Perhaps another '87 model owner can tell you that. If not, you could always add one yourself...
2. Once again, I refer you to the discussion on DUVAC charging systems. What is DUVAC? (https://www.foreforums.com/index.php?topic=33250.0)
In short, IF your alternator and voltage regulator are working correctly, the alternator will put out some amount of charging voltage. The amount will be controlled by the voltage regulator. Whatever the alternator puts out will go to the center post on the battery isolator, and from there it goes to the chassis (start) battery and the coach (house) battery. In a common diode isolator you suffer a loss of slightly less than one volt between the center alternator post and the outside battery posts. So if, for instance, the alternator sends 13 volts to the center post, the batteries will only see slightly over 12 volts, which is not enough to properly charge the batteries. This voltage loss explains WHY you either need a specialized type of alternator (DUVAC) to properly work with a diode isolator, OR you need a way to manually adjust the alternator output to the required voltage.
There are several solutions to the "isolator voltage loss" problem...some are simple and some will cost you more money.
Question: Does your coach have a BOOST switch on the dash?
Here is some light reading:
New battery isolator (https://www.foreforums.com/index.php?topic=31174)
Battery Isolator or auto combiner? (https://www.foreforums.com/index.php?topic=40736)
Charging both House and Start Batteries (https://www.foreforums.com/index.php?topic=36485)
Title: Re: battery not charging 87' GrandVilla
Post by: wolfe10 on January 31, 2021, 02:26:30 pm
The simplest "work around" for a non-DUVAC alternator (one that does not sense voltage on the battery side of a diode-based isolator is a simple marine ON-OFF switch.
Wire alternator output (from B+ terminal) and chassis battery to one lug. House battery to the other. Switch on, both batteries are charged from either alternator or converter or inverter/charger (think of it as a manual boost/combine switch).
Switch off and battery banks are isolated from each other. With engine running, only the chassis battery is charged.
KISS theory!
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 31, 2021, 04:29:29 pm
Folks! We have some progress.
I have voltage reading from the volt regulator when the master switch is on.
When I put the key into the ON position, it doesn't work. All readings are flat.
So it seems to be something else. Thoughts?
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 31, 2021, 04:38:36 pm
When I put the key into the ON position, it doesn't work. All readings are flat.
What doesn't work?
What readings are flat? Where are you taking readings?
You have to be as specific as possible with your description. What are you doing? What is it that does work, and what doesn't work? What is the voltage reading exactly, and where are you reading the voltage? It is difficult to diagnose problems remotely without clear concise information.
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on January 31, 2021, 05:06:06 pm
Sorry about that.
I test the volt regulator A tab when the RV is just sitting there. I am getting the battery reading at 12.75 ( as would be expected. No other wires are « hot ».
I turn the key to the « on » position, and the « A » terminal/tab is dead, so is the « S » terminal.
When in the on position at the key, there is no electricity going to the volt regulator
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 31, 2021, 05:58:48 pm
Can you follow the wires that are connected to the "A" terminal and the "S" terminal to see where they go?
You know what you need to see on the regulator terminals. If the readings are not correct, then you must fix the wiring.
Find a 12 volt source in the engine compartment that is always HOT. Connect it to the "A" terminal.
Find a 12 volt source in the engine compartment that is HOT when ignition switch is ON. Connect it to the "S" terminal.
Then try testing everything again.
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on January 31, 2021, 06:20:39 pm
For doing electrical work like this - especially when trying to track down bad connections or mysterious problems - a set of alligator clip jumper wires is VERY handy. You should have 3 or 4 pairs of these leads in your tool box. They are available from many sources online, and at Lowes and Home Depot and many local electronic supply stores.
Yes, this does give me all I need to know to follow the current system. Yes, It does look just like the alternators on hand.
The remaining two questions....
1. do I have an idiot charging light in the instrument panel somewhere? when all is said and done might be nice to hook up later.
2. Does this alternator have any issue with an isolator after it instead of being a direct connect to the battery?
This is the DASH for our 86 Grand Villa. Lower left corner is the " idiot" voltage gauge... this photo was taken while on a trip with a failing alternator.... we replaced our FORD alternator on a 454 Chevy motor at a CarQuest in a small texas town.
Title: Re: battery not charging 87' GrandVilla
Post by: Subsilked on January 31, 2021, 07:46:51 pm
1. I don't know. Perhaps another '87 model owner can tell you that. If not, you could always add one yourself...
2. Once again, I refer you to the discussion on DUVAC charging systems. What is DUVAC? (https://www.foreforums.com/index.php?topic=33250.0)
In short, IF your alternator and voltage regulator are working correctly, the alternator will put out some amount of charging voltage. The amount will be controlled by the voltage regulator. Whatever the alternator puts out will go to the center post on the battery isolator, and from there it goes to the chassis (start) battery and the coach (house) battery. In a common diode isolator you suffer a loss of slightly less than one volt between the center alternator post and the outside battery posts. So if, for instance, the alternator sends 13 volts to the center post, the batteries will only see slightly over 12 volts, which is not enough to properly charge the batteries. This voltage loss explains WHY you either need a specialized type of alternator (DUVAC) to properly work with a diode isolator, OR you need a way to manually adjust the alternator output to the required voltage.
There are several solutions to the "isolator voltage loss" problem...some are simple and some will cost you more money.
Question: Does your coach have a BOOST switch on the dash?
Here is some light reading:
New battery isolator (https://www.foreforums.com/index.php?topic=31174)
Battery Isolator or auto combiner? (https://www.foreforums.com/index.php?topic=40736)
Charging both House and Start Batteries (https://www.foreforums.com/index.php?topic=36485)
Our 86 GV dash. BOOST switch is top toggle switch highlighted in green in this photo...
Title: Re: battery not charging 87' GrandVilla
Post by: Firewhirrrl on February 02, 2021, 07:24:44 pm
Hello!
Here is what I have at this point.
Charged battery to 12.8
Started RV,
No apparent charging.
Voltage reads 11.79 on both the s and a post, 6.76 on the f post.
Re reading battery: 12.25
Is this enough voltage, or is there enough voltage loss to account for this? Maybe the battery is bad.!
Title: Re: battery not charging 87' GrandVilla
Post by: Chuck & Jeannie on February 02, 2021, 10:23:52 pm
With engine running, check and record the voltage at the following points:
1. The large B (positive) output post on the rear of the alternator. 2. The center (alternator) post on the battery isolator. 3. Both outside (battery) posts on the isolator. 4. The POS (+) post on the start battery.
Let us know what you get for voltage readings.
Title: Re: battery not charging 87' GrandVilla
Post by: Dakota Slim on February 02, 2021, 10:26:27 pm