New Alternator. Still not charging

[Kittykat0505]

Ok so we have a 76 Dodge Appollo m500 with a 440.  Get one problem fixed just to encounter another..so here's the problem. .Battery isn't getting charged when running. .I have replaced the voltage regulator, ballast, AND the alternator..still...have to get a jump every time.  I did a hot field test I guess they call it where I took off the grn fld and attached my ground to it and 14+ volts output. .so I know the alternator has output . . I've gone over the great diagrams that Dave has on the charging system and donew pretty much everything I can think of including exchanging positions of the wires on fld 1 and 2.what am I missing here?  ANY input is welcome. .thanks. .
Kat

[Kittykat0505]

Almost forgot. ..yes. .checked and replaced fusible links off starter relay

[legomybago]

Is your battery good? Have you had it load tested? If it is, the only thing you can really do is chase the electrical with a volt meter starting at the charging source, the alt. Look for a battery disconnect switch hidden somewhere...Or a bad solenoid.

[Rickf1985]

Are you getting 14.5 volts AT THE BATTERY? The alternator may be putting it out but is it reaching the battery? You need to check the voltage at the battery while it is running. If it is actually charging the battery and the battery is going dead quickly then the battery is bad or you have a draw with the key off that you need to track down.

[Kittykat0505]

Thanks for responding. .so rick,  no. .I'm not getting 14.5 at the battery...the alternator only puts out charging volts when we full field it..not when running under normal conditions. .matter of fact I'm now pulled over cause I was driving and turned on my lights and after about 3-4 minutes. .it started to die until I turned off lights.

[Kittykat0505]

Oh and rick. .I can't thank you enough for the advice regarding the distributor conversion.hei with built in voltage regulator. .one wire. .beautiful. .thanks

[Kittykat0505]

starting at the charging source, the alt.

Here in lies the problem. .the alternator only puts out when I full field it..

[Rickf1985]

It sounds like you are not getting the ignition on signal to the alternator. This could be an ignition switch problem. Find the plug on the ignition switch and while it is running move that plug around and see if it starts charging, or even before starting take the plug off and on a couple times to clean up the contacts. Could be a blown fusible link at the battery, I am not real familiar with the Dodge fusible link locations. If you have Daves wiring diagram follow the field wire back to the source, it should be the ignition. If it goes to a fuse or a fusible link anywhere that could be a problem. Also, if it goes through a firewall junction block that has a screw in the center to take the block apart it would be a good idea to do just that. Disconnect battery first. Take bolt out and pull block apart and plug in several times to clean up contacts. A lot of motor homes do not have these so if you do not see it where the wire harness goes from outside to inside do not worry about it.

[PwrWgnWalt]

My similar-vintage Beach-Craft had a "battery isolator" (Google that for a picture) inline between the alternator output wire and the batteries. It was mounted in the nose of the MH, by the coolant overflow bottle cap. This takes the place of the above-mentioned manually operated battery disconnect 'solenoid'.
I had the same problem you are experiencing, with a no-charge situation, when I first got my MH.
First, I discovered the battery isolator was no longer working properly, and is slightly inefficient due to its old-style diode design.
Second, I decided to trace down all the wiring to the battery compartment... I found a compromised/broken wire. Did this with an inexpensive Harbor Freight 'free with purchase' multimeter (set to Ohm's for resistance, & you never want to pass current/voltage through it on this setting). I used a long piece of wire to extend one of the leads from the front of coach back to battery bay under the door step.
I decided to go another direction with my charging system but it was not necessary, just convenient.
Lastly, I read others' experiences about frying the voltage regulator/alternator by running the engine while being connected to shore power or on generator, so I never do that.  I did replace my voltage regulator (VR) when doing all of my work.


Don't know if this will help, but whatever your MH's method for connecting the alternator to the battery, I would start testing circuits for continuity and work from there. If the Alternator is known good, next checks would be the VR and the wiring.

[Rickf1985]

Ok, I was looking at Daves wiring diagram and I need to know if you have voltage at the main batt terminal on the alternator with the engine and ignition shut off.

http://dave78chieftain.com/Charging_TS.html

Is this the link you followed from Dave? This should get you where you need to be. Be sure the voltage regulator is grounded and be sure all of the voltages are within the ranges called for in this article.

[Kittykat0505]

Thank you so much for all the info. .I've been thinking it's got something to do with the ignition and the battery isolator .I can't seem to find the isolator on this thing yet. And when we got it the previous owner had no key so he did God only knows what to the ignition switch cause you can put any key in it to start it. .but.. to answer your questions. Yes ric that is the diagram I've been using and yes I have voltage at the battery terminal on the alternator with the engine and ignition off.

[Rickf1985]

And do you have battery voltage to the "I" terminal of the voltage regulator with the ignition on? If you do then the battery should be charging normally. Those things would show that the battery is connected to the alternator and the ignition switch is connected to the regulator. You already said you could full field it and it would put out full charge. This is all pointing to a regulator problem. Run a jumper wire from the battery ground terminal to the regulator body to make sure it is grounded. If this does not work I would say the regulator is bad.

Wait a minute here?! You say you have 12 volts at the charging terminal of the alternator right? But you say if you full field it you get 14.5 volts out but it is not getting 14.5 at the battery? Verify that please. If it IS getting 14.5 at the battery with it full fielded then the regulator is bad.

[turbinebronze]

Isn't this a Chrysler electronic voltage regulator?  If so, the field wire you grounded at the alternator (when you full fielded the alt, and it worked) will run to the voltage reg.  The voltage reg just controls the grounding of the alt, just like you did.  (On the old Dodge trucks it was a green wire).
  The other wire at the voltage reg. will be a battery sense wire (Old Dodge truck, blue wire). With the key on, engine not running, voltage reg connector not hooked up, both wires at the voltage reg should be battery voltage.
  A broken wire between the reg and the alt will stop the alt from working. And there would be no voltage at the reg plug on that wire.
  If the voltage reg is not grounded, the alt will not charge.
  Hope this helps, Craig.

[DaveVA78Chieftain]

Apollo's were high end rigs in that era so I suspect you have a battery isolator in the circuit (Alt B+ output).  Most likely located in the engine access area in front of the rig.  You may even have a Battery Control Center up front (engine access area) that the alternator output is routed through that has a battery isolator relay.  Just saying, Apollo design would be more fancy than Winnebago in that era.


The signal from the ignition switch to the "I" terminal of the regulator is the "sense" signal that the regulator uses to adjust the amount of current flows through the "F" terminal to ground.

[Kittykat0505]

Would it do any harm. .short term that is if I just run the battery positive through the voltage regulator straight to the battery? Cause I understand completely how it's supposed to work but I am not having any luck making it work. .the wires are such a mess and a good portion of them were melted. .I can't find the battery isolator. ..I have yet to figure out the wiring for the coach. .considering most of what I've read on this site references this  battery isolator. .I'm thinking that's an issue since I can't find it. .the previous owner right before I took possession had cut out all the wires to the batteries and had the ignition wires cut..so I'm wondering if it's possible that the b.i. is missing too. Should I just get an isolater..and start over and run new wire for the charging system?  I have the ability,  and I understand how it's supposed to go. ??

[Rickf1985]

The battery cable does not appear to be your issue, You have battery voltage at the alternator terminal, The issue appears that you are not getting battery signal voltage through the field which would normally come through the ignition circuit. What you could do is go by the diagram and run a bypass wire from a battery source to a switch and from the switch to the field terminal on the alternator. The switch would be in place of the ignition switch on the diagram. Here is the big problem with that scenario, if you forget to turn off the switch it will drain the battery pretty quickly. The better way to do it would be to use a common relay you can buy on Amazon with the plug and wire it into the field circuit as using the relay as the switch and using the ignition coil as the trigger for the relay. This way it turns on when the engine is on and off when the engine is off.

You can get those relays in a parts store also, you don't have to have the plug but it makes it easier.

Here is what the relays look like.

https://www.amazon.com/Pack-EPAuto-Relay-Harness-Bosch/dp/B017VDI0GY/ref=sr_1_1?s=automotive&ie=UTF8&qid=1471184452&sr=1-1

[DaveVA78Chieftain]

1) You have ignition switch voltage to the distributor.
2) You have battery voltage to the starter solenoid B+ terminal.  Has to be there so the e=starter relay will engage.

So,
The distributor 12 volt supply becomes your source for the charging system.  Actually the system was already designed that way originally so, we are just duplicating that set up as shown in the drawing above.
1) Run a new 16 or 18 gauge wire from the distributor 12 volt source to the "I" terminal of the alternator regulator.   The "F" terminal is the return path for the alternator from the lower FLD wire from the alternator.
2) Run second new 16 or 18 gauge wire from the distributor 12 volt source to upper alternator FLD wire.
3) Make sure the regulator case is grounded (mounting bolts area is clean ans shiney).
4) Run a new 10 gauge wire from alternator B+ to the B+ terminal at the starter relay (mounted on drivers side frame rail).  This is the same terminal the chassis battery B+ cable connects to.  I would duplicate the original design by installing a fusible link on this wire at the starter relay for safety. BTW, that fusible link may have failed which is why you are not getting voltage to the B+ starter relay post.  Unless there is a diode failure in the alternator, Dodge does not drain the battery when the alternator B+ is connected to the Battery B+.

Given the problems with your original wiring, what I described is nothing more than duplicating the original Dodge design as shown in the wiring diagrams.  The picture above is based on the early (pre-74) setup that had a dash mounted ammeter in series with the ignition circuit.  The ammeter had a bad habit of failing which resulted in a no run condition so, Dodge changed the design in late 73 such that the ammeter was no longer in series with the ignition switch B+ supply.  They started using a shunt based ammeter instead. 

If you do not have the Dodge wiring diagrams you are making this painful for yourself.  They are available in the Dodge manuals in the site store.

Dave

[Rickf1985]

Do what Dave says, Not me. I realize that I totally forgot to include the voltage regulator in my design!! DOH!!! I have been working on GM and Ford to much.

[Kittykat0505]

Ok..I'm armed with all the diagrams and these instructions and I'm going to see what I can do..yes dave of course I have the wiring diagrams which I got from your site actually. .so ric you said that because I don't have voltage through the field it comes from the ignition is that correct or was that where the voltage regulator comes into play?  Cause the  ignition wiring is pretty hacked up..
Ok well thank you dave for your instructions. .in gonna get to work and I'll let you know how it turns out..or if I have any more questions. .thanks again.
Kat

[Kittykat0505]

Uh oh..Dave, I have a question. .maybe you don't remember the help I got from you and ric a while back regarding my distributor..instead of an electronic distributor. .the guy who owned this had put in a points distributor so alot if things were eliminated. . (I've got the one wire hei with built in regulator scheduled to arrive Thursday )..but I don't have the dual ballast resistor anymore and I don't have an the ignition control module anymore. .so when you say to use the distributor 12v source. .I'm a little confused as to what you mean since the only wire to the dist. is through the coil from the ballast  .

[DaveVA78Chieftain]

Assuming you purchased this HEI distributor:
https://www.amazon.com/Brand-Distributor-Plymouth-Chrysler-DDBB-DF/dp/B00WCXRSB2

Then,
That HEI distributor
1) Does not use a ballast resistor,
2) Has the coil built in to the top of the cap so no external coil is required, and
3) Only has a one wire hookup directly from the ignition switch (12VDC). 
Do not confuse that much newer GM HEI design with the older points or Dodge Electronic Ignition design you are replacing.  The GM HEI is a completely different, but simpler, design.

That wire from the ignition switch would also be the 12VDC B+ source to regulator pin "I" and the B+ to the upper field wire on the alternator.

[Rickf1985]

Dave, question on that last statement. You say the wire from the ignition switch would be the source TO the regulator AND the B+ terminal of the alternator? Are you sure that is right? I believe the B+ terminal is direct to the battery through a fusible link and the ignition switch branches off of that and feeds the I terminal on the regulator and the rest of the ignition related power. If it were to go from the switch to the B+ that would mean all of the charging current would be going through the ignition switch.

[DaveVA78Chieftain]

Picture is worth a 1000 words

[Rickf1985]

And there you have it, now you can build your own ignition system. Keep in mind that you do NOT have to have a key switch. You can have something as simple as a on/off switch for the ignition (Think turning the key on) and a push button to start the engine. (think turning the key to start) the push button is all the rage nowadays in cars. For security all you need is one switch that is hidden somewhere that is inline with the ignition switch. If that switch is not turned on then no go.

[Kittykat0505]

Sorry for the delay in getting back to you....yes Dave that is the HEI dist. that I've purchased and of course..Amazon is taking its time..I was hoping to use the diagram you posted and rewire it with new dist. but it's not here yet and I need to get this charging system fixed asap. So I've gotten new wire and I'm going to follow the original wiring for now...I know the starter relay is good, alternator puts out under full field test..I did buy new voltage regulator and I just got a ballast today for the points distributor..so unless there's anything else I think I'm armed with everything I need to run new wire...thanks for all the info..Ill be working on this first thing in the morning so I'll let you all know what happens..keeping fingers crossed