Los_Control Posted January 26 Report Posted January 26 (edited) Wiring up my charging system and I'm confused as what to do with wire #3 on the voltage regulator. I have a factory ACDELCO replacement plug for the VR .... All 4 wires are 16 GA I'm afraid if I were to connect 16 GA wire to the main lug of Alternator, would eventually melt. Obvious this is not a factory wiring diagram .... the factory shows it also 10GA with a short piece of 16 GA fusible link and connected to the battery post. From what I have read, it serves as voltage sensing .... Here is a version of the original wiring. Again they say to use 10 GA wire with a 14 GA fusible link to the battery. .... It is just the wire size I'm confused on because the plug coming out of VR is 14 GA not 10. Does it matter if I just run 10 GA to the 14 GA and have it the fusible link on the VR side? Everbody says 10 GA but the factory ACDELCO plug is only 14 GA ... Edited January 27 by Los_Control Quote
Sniper Posted January 27 Report Posted January 27 2 hours ago, Los_Control said: Does it matter if I just run 10 GA to the 14 GA and have it the fusible link on the VR side? the fusible link protects everything connected to the splice, not just the regulator and you want the link as close to the battery as possible to protect the wiring as well. 10 ga. seems overkill for the regulator, heck that's the same size as the feed to the battery. Quote
Los_Control Posted January 27 Author Report Posted January 27 Thanks for the help @Sniper does this make sense? I want the Alternator to join on the outgoing side of the amp gauge and will run 10GA from Alt to there. Then run from the VR to the same post using it as a junction block with 16 GA ... just continue with 16 GA the vr already has. Hard to draw with a mouse, but is the general idea I'm thinking of. Quote
Sniper Posted January 27 Report Posted January 27 With the understanding that I don't do GM charging systems, I don't see a problem with that. Where are you going to put the fusible link? Quote
Los_Control Posted January 27 Author Report Posted January 27 15 hours ago, Sniper said: With the understanding that I don't do GM charging systems, I don't see a problem with that. Where are you going to put the fusible link? Sadly I'm a bit too far invested into this GM charging system .... I thought I was ordering a 1 wire internally regulated alternator .... so my charging system is a mistake to begin with .... but I have it now. And all the needed goodies to complete it. It should be fine once all is sorted out. Just the darn Voltage sensor wire where all are saying 10 ga and the factory wiring harness has 14 ga. So my thoughts are to just install a inline fuse of 15 amp. Internet tells me to use 15 with 14 wire. Actually tempted to run it through the fuse box .... I just do not understand the wire that much. It is always connected with the main 10 ga wire from the factory or the other diagram I showed .... so I'm just connecting it under the dash with the same wire because I do not know any better. I'm not using a fusible link, because would prefer to have the option to just change a fuse if needed. .... I only assume that is fine? Quote
Sniper Posted January 28 Report Posted January 28 (edited) The major difference between a fuse and a fusible link is that a fusible link will tolerate an overload for longer than a fuse will. So if you have the occasional spike it won't blow. Since I do not know exactly how the GM charging system works I can't really say how much current that voltage sensing line uses. But I do not think it is directly involved in the field current necessary for the alternator to charge. I kind of suspect it's the on-off switch and something else handles the current the alternator requires to start charging Edited January 28 by Sniper Quote
Los_Control Posted January 28 Author Report Posted January 28 6 hours ago, Sniper said: But I do not think it is directly involved in the field current necessary for the alternator to charge. I kind of suspect it's the on-off switch and something else handles the current the alternator requires to start charging They call #3 a voltage sensing wire? #4 is connected to ignition switch or coil .... it provides the 12V needed to make it charge? To early to put the plastic sheathing on. I think I can make it kinda clean with the fuse holder poking out of the sheathing as it is in the photo. The only thing left for the charging system is to connect the after market Voltage gauge .... then I can start the truck up and verify it works or try something new. Been spending time making the dash gauge wire harness and mounting the fuse panel. and hope to be able to start it by the end of the day ... using the key. I have a 12V > 6V converter to wire in for the fuel gauge .... I wired the sending unit a year ago and am hoping I marked the ground wire .... all bundled up under the cab with the tail light wires. I tested the speedometer on the bench with a drill .... before installing it, needle never moved so it has internal issues .... need to dig out the spare and test it. Everything always takes longer then I think it will 😕 Quote
Sniper Posted January 29 Report Posted January 29 (edited) You are a scallywag. 😄 You made me dig up the paper on the GM 10DN charging system and read thru it, bottom of the page. Some archaic terminology was used, but hey that's ok the Navy taught me electronics and it's tech was even more archaic in some cases (AN/SPS-10 radar). So I understood it, I think, lol. You have what Delco calls a Two-unit regulator with indicator lamp. This drawing shows how to wire it, EXCEPT #4 needs to go thru an idiot light and parallel resistor (no value given for the resistor) if you want an idiot light, otherwise nothing gets connected there and 2 gets the switched 12v. Number three should be wired to as close to the battery as possible. This is the wire that controls battery charge voltage and taking it off the BATT terminal at the alternator is less than ideal. Although an engineer or a theorist will tell you that both points are "electrically identical" reality says any connection or splice between the two will create resistance and cause an effect. Since this charging scheme is fairly primitive in reality I don't think it matters enough, in other words it's likely to be within the regulator's margin of error anyway. Unless it's a really crappy connection. 10DN with ammeter wiring (you can run this sans ammeter and no light) 10DN with light Edited January 29 by Sniper Quote
Los_Control Posted January 29 Author Report Posted January 29 11 hours ago, Sniper said: You are a scallywag. 😄 LOL .... I read your post at 4:00 AM and no chance of going back to sleep .... I would like to return the comment The diagram you show does look good to me and I think I will try it. .... It looks old and I can smell the must coming off the 50 year old book. Meeting at the junction (starter solenoid) will be fine and it is connected to the battery. The only problem I see with that is running the alternator through the amp gauge .... I suppose it is a opinion and has been done both ways for many decades. Interesting the relay connector on back of alternator does not get used .... only used if you have a idiot light ... I do not. I have been so worried about protecting the 14 ga wire with a fuse .... the diagram I showed has the #12 fusible link on the 10 ga wire which I did not protect. Not sure how much I will get done today, I do have to go to town and plan to pick up the fusible link while there .... wife wants to adopt a dog from the pound. No idea how that is going to go and what time I will have to work on the truck. Quote
Sniper Posted January 29 Report Posted January 29 Yes, just so you know I drove up to Amarillo and back yesterday thinking about this the whole way and when I got home I dug up that paper and figured out what was going on. Good luck and let us know how it goes. 1 Quote
Los_Control Posted January 29 Author Report Posted January 29 Well I used this one right here .... Thanks for finding it, when I search I always get the same one I posted above. I can say no fires were started .... I think it is charging .... Time will tell. I checked the battery before starting ... it was 12.4 volts. At idle the truck showed 13.2 volts Not the 14.4 volts I want to see, but the battery really was not discharged so maybe 13V is all I should see. I will leave it as is for now and next move on to the dash lights, volt gauge, fuel gauge, running lights. The headlights, dimmer switch, turn signals should be extra fun 🙄 I planned on two 2 wire flashers and today I see my sigstat 900 switch wants one 3 wire flasher .... One circuit at a time. Quote
Sniper Posted January 30 Report Posted January 30 Glad you got it working. 13.2 volts is not an uncommon voltage to see. Quote
Los_Control Posted February 25 Author Report Posted February 25 Honestly, I thought this thread would be pages long by now ... actually it has gone pretty smooth. I have ignition, charging, headlights, dash lights finished .... kinda. I really wanted a junction block so the front end can be removed if needed in the future ... like factory but different. Think I need to build a cover for this junction block. Little concerned my high beam indicator is not working correctly .... I will figure it out. I have changed twice on how I want the main charging wire connected to the system .... I have tried to keep it from running through the amp gauge and come in after the gauge .... the amp gauge just works backwards when I do. Now I'm taking it straight to the battery, then to the starter solenoid, to the fuse panel, to the amp gauge to the ignition switch. Modern wiring, the amp gauge is really the end of the line and just not needed with a volt gauge and a fuse panel ... I'm trying to keep it in line and relevant .... just not easy. I assume the charging system will run through the amp gauge in a round about way .... I just have not figured out a better way to include it and have it read correctly. I will change that around tomorrow, and then I'm working on the turn signals and brake lights ... that should complete it for now. Quote
Sniper Posted February 26 Report Posted February 26 In the factory setup the only thing the amp gauge indicates is the charge going to or from the battery. If you want it to work like that you have to wire all your loads and the output of the alternator to one and meter stud the other stud goes to the battery. If it reads backwards you need to swap the wires on the studs. 1 Quote
Los_Control Posted February 26 Author Report Posted February 26 I purposefully put the charge wire on the outgoing side of the Amp gauge, so the full charge would not run through the gauge. Now the gauge reads backwards as the flow is stronger ... flip the wires around would fix that, then the full charge would flow through the gauge .... what I was trying to avoid. So I decided to move the charge wire to the battery, this still puts charging before the gauge. Where I'm confused or undecided .... there is no place for the Amp gauge to flow to. This is currently what am thinking of ... after looking at the drawing, would be better to move the feed wire from the starter solenoid to the amp gauge, and feed the gauge from a slot in the fuse box. I can protect it with a 25 amp fuse and then run the exit ware as shown, back into the fuse box feed .... just run it in circles? Would be more simple to just use the volt gauge and leave the amp gauge disconnected. The other morning I started the truck and since I had ran the battery down while testing lights ... The volt gauge showed just over 14 volts ... working fine. Today I plan to be 100% finished under the hood ... all cleaned up and wrapped up. Then move back to under the dash and sort out the turn signals/brake lights and do something with the amp gauge. Quote
Sniper Posted February 26 Report Posted February 26 I'm not sure exactly what you mean by full charge running through the ammeter. The ammeter is supposed to read the charge going to or coming from the battery and it's virtually instantaneous indication of the status of your charging system. Because if you're driving down the road and it's reading negative you're charging system is not working. I'll voltmeter is somewhat slower to react and usually what happens is you notice darn my headlights are really dim then you look at the ammeter and you're down around 11 volts in which case you better be looking for a place to park. Or you can run that indicator light from your alternator as an instantaneous indication that it's not working. Quote
Los_Control Posted February 27 Author Report Posted February 27 What I mean is .... A typical Amp gauge reads about 30 amps, then it is pegged out and may actually burn out if exposed to more then 30 amps. My cheap 1972 Chebby alternator is small and is only capable of putting out 65 amps .... twice what the 1949 Dodge amp gauge should see. And that is the rub .... some people will say they have been running a alternator through the amp gauge for 20 years and never had a issue. While others will say they did the same and they fried the gauge out. ... Just smoked it like a fuse and that left them sitting without a complete electrical circuit. So my goal was/is to not run the charging system load through the amp gauge .... I just see myself late at night with it snowing, the heater going full blast, the head lights on high beam and the radio blasting and wipers working .... and run too big of a load through the amp gauge and blow it out. All of this is impossible because I live in Texas and it does not snow, I do not use the heater, my wipers are vacuum and I do not drive at night .... there is still the possibility though So now I'm just unsure of what to do with the amp gauge ... considering to just run it in a loop so it appears to be functional and reads positive when engine running ... probably be better off to just ignore it and not connect it at all. Screw that .... what about the horn? .... hard to get motivated today. I did manage to install the steering wheel and fish the horn wire through. Can not really wrap my head around wiring it up. My horn is not original, the body is mounted on a bracket, the bracket is mounted to the car and the bracket is also ground for the horn. Then a hot wire is ran to the horn to activate it. IIRC, the horn button on a positive ground system is a ground ... I'm thinking I may need a relay to run the power wire from the horn to, then the wire from the horn button to the relay and also a hot wire to the relay .... then when push the horn button it will complete the circuit and honk. I know if I had a button that I ran power into and then out to the horn ... when I pushed the button it would honk. Just can not figure out how to connect power to the stock horn button, with only one wire coming out of the bottom of the steering column ... do I need a relay for this? Quote
Sniper Posted February 27 Report Posted February 27 4 hours ago, LazyK said: Horn is a high current load,relay needed. Yes and the high amp feed for that relay would bypass the amp gauge. Quote
Los_Control Posted February 27 Author Report Posted February 27 Nothing like spending two days on wiring a frigging horn 5 hours ago, LazyK said: Horn is a high current load,relay needed. I do agree with you, same time I have connected horns without a relay and just a push button to fire the horn so a car could pass inspection. Not ideal but they worked fine and never caused a issue in the past .... mind you these were friends vehicles that asked for help and brought the materials needed to connect them .... I never have done that on my own vehicle. What is really confusing me is the original horn button works off of positive ground ... My "temporary" horn is 12V negative ground and it is grounded by simply mounting it to the cab. Is simply obvious that if a hot wire was connected to the horn it would be stuck on ..... the original horn button would have zero effect .... After spending the day reading about relays and how to use one to wire a horn .... I'm finally starting to understand that the relay will have power to it, and will be functional when the ground from the horn button is pressed .... I'm still skeptical and waiting for the final outcome. I did spend a few minutes and made a holder for the relay ....I'm certain it will look old and factory with the wires coming from it Tomorrow, day 3 ... I will actually wire it and test it. Been playing Texan today, is only 67 degrees and a breeze blowing for wind chill .... in the shop with a sweatshirt and propane heater on .... back into 70's tomorrow. Quote
LazyK Posted February 28 Report Posted February 28 (edited) You will need power to terminals 30 and 86. horns to terminal 87. Steering wheel horn switch lead to terminal 85. Make sure the relay is rated to 30 amps minimum. If you want the horns to only operate with the key on you would power terminal 30 from a constant power source(battery) (per Sniper before the amp gauge) and terminal 87 from the acc terminal on the key ignition switch Edited February 28 by LazyK Quote
Sniper Posted February 28 Report Posted February 28 Old school relays like the one in your truck originally don't care about polarity. Newer ones do if they have a diode in them. All's it is is a coil that generates a magnetic field and closes your contacts. The old school relay will generate that magnetic field being fed either way. A later relays with the diode I mentioned have those diodes for noise suppression more than anything else and in your truck there's nothing to worry about if there's noise on the line. Quote
oldodge41 Posted February 28 Report Posted February 28 (edited) Modified schematic assuming your truck horn switch is still creating the ground for the relay. Edited February 28 by oldodge41 add info Quote
Los_Control Posted February 28 Author Report Posted February 28 Now all ya all got me thinking some more. There are a few different ways to wire the relay. You can watch the video if bored, but you can see how it is wired from the image. pin 30 and 86 both get power from a single source ... I'm thinking 14 gauge wire with a 20 amp fuse ... looks like 14 gauge on pin 87 also, then just 16 gauge on the others. Where the relay is mounted right above the starter .... will be a short run from the solenoid straight up to the relay. Now I'm wondering, if I used a separate wire from the ign switch to pin 86 ... the horn would only function with the key on? I see advantages to both ways ... simple and easy this way ... for safety reasons ... I can think of many reasons to use the horn without key on. I can also remember the days when a horn button would malfunction in a parking lot, while owner was inside shopping. This would be avoided if the key was not on. ... I think I like this way best. Quote
Los_Control Posted March 1 Author Report Posted March 1 OK I wired it like suggested with 86 being switched from the ignition .... the horn only works with the key on. .... I think that is the best way for me. Horn works fine except for the horn malfunction .... the horn works when button is pressed .... the old bakelite button and the freshly painted wheel sticks and does not always return fully ... not a big deal. I finally did get to move forward and tomorrow I will be inside under the dash fixing things as they should be. I just laugh because I always said .... For the 6 wires this truck needs to run, will just build my own harness. ..... boy did I miscount the needed wires. While not 100% finished ... it is pretty close. As usual, I do have one lazy light No idea why the right side marker light is not on .... will fix it tomorrow .... I know it does work. Things are moving forward though .... tomorrow will be a special treat when I start connecting the turn signals and brake lights 🙄 2 Quote
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