DJK Posted August 1, 2020 Report Posted August 1, 2020 Has anyone converted a GM 10Si 12v alternator to 6v pos ground? My generator checks OK, new battery, new O gauge cables, new V/R, after 10 mins. of driving stops charging. Went back to electrical shop, that said I needed a V/R originally, said they cleaned contacts in new V/R!!!!!!! While driving to a cruise in yesterday, stopped charging after 10 minutes or so, never charged all the way home, 70 mile round trip. Quote
Los_Control Posted August 1, 2020 Report Posted August 1, 2020 https://www.qualitypowerauto.com/item_24/6-Volt-Alternators-Positive-Ground.htm Quote
Los_Control Posted August 1, 2020 Report Posted August 1, 2020 Glad you made it home without a flatbed While there are 6 volt positive ground alts available for $134 last I checked, Just saying why convert when you can buy for reasonable price? I had to walk into office to get the link and send it, then back to the shop to finish post Quote
50mech Posted August 1, 2020 Report Posted August 1, 2020 Might be stating the obvious here but after ten minutes or so your ammeter should show very low to no charge. Just means the battery is fully up. If that's what's happening your charging system is actually fine. Any issues restarting, or low battery or anything else to indicate a non functional system? 1 Quote
DJK Posted August 1, 2020 Author Report Posted August 1, 2020 5 minutes ago, Los_Control said: Glad you made it home without a flatbed While there are 6 volt positive ground alts available for $134 last I checked, Just saying why convert when you can buy for reasonable price? I had to walk into office to get the link and send it, then back to the shop to finish post Luckily I didn't need headlites!!! The conversion kit is around $40 and an alternator from Rock Auto is $21 and up depending on what you want to spend. I just thought it would be fun to do it myself. Just curious if anyone is using one. Quote
DJK Posted August 1, 2020 Author Report Posted August 1, 2020 3 minutes ago, 50mech said: Might be stating the obvious here but after ten minutes or so your ammeter should show very low to no charge. Just means the battery is fully up. If that's what's happening your charging system is actually fine. Any issues restarting, or low battery or anything else to indicate a non functional system? When I put a voltmeter on battery it drops below 6v with loads on. Also while driving home I turned the headlites on, ammeter went more neg., blower motor and defrost motor on went even more neg., so I'm pretty sure it is not charging. I started it today, same thing no charge indicated on ammeter and more loads more negative indication. 1 Quote
50mech Posted August 1, 2020 Report Posted August 1, 2020 (edited) Yep, just making sure. Sounds like a fun puzzle but if you're switching it out then I guess no need to try haha. First guess would be cutout relay in the VR needing adjusted. Edited August 1, 2020 by 50mech Quote
DJK Posted August 1, 2020 Author Report Posted August 1, 2020 The frustrating part is that it is a brand new VR. Quote
Los_Control Posted August 1, 2020 Report Posted August 1, 2020 2 minutes ago, DJK said: Luckily I didn't need headlites!!! The conversion kit is around $40 and an alternator from Rock Auto is $21 and up depending on what you want to spend. I just thought it would be fun to do it myself. Just curious if anyone is using one. I like to learn new things everyday, I have never heard anyone talk about converting a 12 volt alt to 6 volt. I learned something today thanks to you, I did not know when I woke up. Like any troubleshooting, I figure it is best to start at the beginning, remove the VR out of the pic by disconnecting the wires, check the alternator with a multi meter to see is producing a charge. Then next step forward to connect VR and check from there. I have no experience with what you are doing, but I worry about cheap china electrical parts like condensers & points, doa out of the box or work one time and condenser fails. You drove 10 miles and it stopped working .... get the vr out of the picture and prove the alternator is charging first. Quote
Sam Buchanan Posted August 1, 2020 Report Posted August 1, 2020 (edited) 3 hours ago, DJK said: Has anyone converted a GM 10Si 12v alternator to 6v pos ground? My generator checks OK, new battery, new O gauge cables, new V/R, after 10 mins. of driving stops charging. Went back to electrical shop, that said I needed a V/R originally, said they cleaned contacts in new V/R!!!!!!! While driving to a cruise in yesterday, stopped charging after 10 minutes or so, never charged all the way home, 70 mile round trip. In far less time that it would take to figure our how to redo an alternator, this reliable vendor can have an alternator that is ready to bolt to your car at your door in 3-4 days: https://www.ebay.com/str/HowardEnt?_trksid=p2047675.l2563 I have had flawless service from the alternator I purchased from Howard. Notice their price includes shipping which is an extra $40 with some vendors. https://www.ebay.com/itm/Tractor-car-6-volt-60-amp-1-wire-alternator-Positive-Ground-w-Bracket-pulley/333591006902?hash=item4dab92ceb6:g:Y~QAAMXQobdQ7d68 Edited August 1, 2020 by Sam Buchanan Quote
Sniper Posted August 1, 2020 Report Posted August 1, 2020 Replacing the generator may not resolve your issue. It sounds like something is getting hot and causing the charging failure, since your ammeter appears to be working properly (shows more discharge when you turn the lights on) I wouldn't start there, wiring from the gen to the ammeter though, it could be that, heck it could just be a loose connection at the generator. If you have an IR gun you can shoot temps of the various parts and see if anything seems out or place. Or better yet, shoot temps before it quits, writing them down and then once it quits shoot again. Though it could be the VR or the generator anyway which the swap would fix, but I'd do some troubleshooting before i spent a lot of money. 1 Quote
DJK Posted August 2, 2020 Author Report Posted August 2, 2020 4 hours ago, Los_Control said: I like to learn new things everyday, I have never heard anyone talk about converting a 12 volt alt to 6 volt. I learned something today thanks to you, I did not know when I woke up. Like any troubleshooting, I figure it is best to start at the beginning, remove the VR out of the pic by disconnecting the wires, check the alternator with a multi meter to see is producing a charge. Then next step forward to connect VR and check from there. I have no experience with what you are doing, but I worry about cheap china electrical parts like condensers & points, doa out of the box or work one time and condenser fails. You drove 10 miles and it stopped working .... get the vr out of the picture and prove the alternator is charging first. It's a .generator to begin with, all original with brand new made in USA VR. I am just curious if anyone has any experience with the 6v pos ground alternators. I did not know about the conversion kits until today, been a long time since I've had an alternator apart and even longer time since messing w/ gens and VR. Quote
DJK Posted August 2, 2020 Author Report Posted August 2, 2020 1 hour ago, Sam Buchanan said: In far less time that it would take to figure our how to redo an alternator, this reliable vendor can have an alternator that is ready to bolt to your car at your door in 3-4 days: https://www.ebay.com/str/HowardEnt?_trksid=p2047675.l2563 I have had flawless service from the alternator I purchased from Howard. Notice their price includes shipping which is an extra $40 with some vendors. https://www.ebay.com/itm/Tractor-car-6-volt-60-amp-1-wire-alternator-Positive-Ground-w-Bracket-pulley/333591006902?hash=item4dab92ceb6:g:Y~QAAMXQobdQ7d68 Sam that is a great price for alt/bracket/shipping. thanks Quote
DJK Posted August 2, 2020 Author Report Posted August 2, 2020 1 hour ago, Sniper said: Replacing the generator may not resolve your issue. It sounds like something is getting hot and causing the charging failure, since your ammeter appears to be working properly (shows more discharge when you turn the lights on) I wouldn't start there, wiring from the gen to the ammeter though, it could be that, heck it could just be a loose connection at the generator. If you have an IR gun you can shoot temps of the various parts and see if anything seems out or place. Or better yet, shoot temps before it quits, writing them down and then once it quits shoot again. Though it could be the VR or the generator anyway which the swap would fix, but I'd do some troubleshooting before i spent a lot of money. The generator has been checked twice(in the shop), VR new and points cleaned once already!!!??? by the electrical shop where purchased. Wiring appears OK(68 yrs. old). I will perform a load/wiggle test on the harness this week before condemning any components. Quote
Sniper Posted August 2, 2020 Report Posted August 2, 2020 Well, if the ship hasn't fixed it after two checks I'd not rely on that myself. But I am a natural born skeptic. Quote
maok Posted August 2, 2020 Report Posted August 2, 2020 As has been mentioned, check all your connections, and how old is your battery? Quote
DJK Posted August 2, 2020 Author Report Posted August 2, 2020 6 hours ago, maok said: As has been mentioned, check all your connections, and how old is your battery? Brand new battery, new 0 gauge cables, gen checks OK, new made in USA VR, shop "cleaned points" in VR once already!!!!???? I will perform a wiggle/load test on the harness this week before I condemn any component. Quote
DJK Posted August 3, 2020 Author Report Posted August 3, 2020 Just load tested and wiggle tested the harness, all connections OK, gen puts out when grounding field terminal. Getting money back for VR and ordered 6v pos ground alt from Howard Enterprises. Quote
James_Douglas Posted August 3, 2020 Report Posted August 3, 2020 (edited) I purchased a 6 volt positive ground 10SI self exciting alternator from these folks and a small pulley: https://alternatorparts.com/6-volt-alternators-negative-positive-ground.html That was 15 years ago. It has worked without issue. You MUST rev the engine after you start it up to get the thing to start charging. It uses one wire and that is it. I purchased a spare voltage regulator, which goes inside these units and have never had to touch it. It has worked as my daily driver in the cold and dank San Francisco fog and at my place in the Central Valley in days of 105F heat. James. Edited August 3, 2020 by James_Douglas Quote
Sam Buchanan Posted August 3, 2020 Report Posted August 3, 2020 (edited) 16 minutes ago, James_Douglas said: I purchased a 6 volt positive ground 10SI self exciting alternator from these folks and a small pulley: https://alternatorparts.com/6-volt-alternators-negative-positive-ground.html That was 15 years ago. It has worked without issue. You MUST rev the engine after you start it up to get the thing to start charging. It uses one wire and that is it. I purchased a spare voltage regulator, which goes inside these units and have never had to touch it. It has worked as my daily driver in the cold and dank San Francisco fog and at my place in the Central Valley in days of 105F heat. James. The one-wire alternator I have starts charging immediately after start. I agree that it is a reliable solution to keeping the battery fully charged in our old cars under all conditions. A hot battery and the proper cables solves a lot of starting issues! ? Edited August 3, 2020 by Sam Buchanan 1 Quote
DJK Posted August 10, 2020 Author Report Posted August 10, 2020 Just installed my alternator from Bill Howard Enterprises. Started charging immediately, ammeter shows positive. Feeling more confident to do some driving, just need to verify source of oil leak on back of engine and repair. Thanks for all the help. 1 Quote
Sam Buchanan Posted August 10, 2020 Report Posted August 10, 2020 (edited) If you don't already have the proper size battery cables in excellent condition, go ahead and upgrade. The alternator and cables will make your charging system as good as it can possibly be. Excellent source for cables is BatterycablesUSA. Edited August 10, 2020 by Sam Buchanan Quote
DJK Posted August 11, 2020 Author Report Posted August 11, 2020 18 hours ago, Sam Buchanan said: If you don't already have the proper size battery cables in excellent condition, go ahead and upgrade. The alternator and cables will make your charging system as good as it can possibly be. Excellent source for cables is BatterycablesUSA. Sam, my local shop made me 3 "0" gauge cables that look identical to yours except my pos . cable is red, neg is black Quote
Sam Buchanan Posted August 11, 2020 Report Posted August 11, 2020 1 hour ago, DJK said: Sam, my local shop made me 3 "0" gauge cables that look identical to yours except my pos . cable is red, neg is black Excellent. My cables are also red/positive and neg/black. Quote
DJK Posted August 12, 2020 Author Report Posted August 12, 2020 12 hours ago, Sam Buchanan said: Excellent. My cables are also red/positive and neg/black. I just noticed your alt is neg ground!!!! Quote
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