Hi guys, I recently replaced the 12v generator with a Delco one wire alternator on a 1963 Ford truck with a 292 engine. I connected the output wire from the alt to the existing Batt wire on the old regulator, and eliminated the regulator and the other wires. It charges, but when ignition is off, it drains the battery overnight. What did I do wrong?
- Thread starter farmboy48
- Start date
buickanddeere
Well-known Member
The alternator is a dud. Are there are excitation and voltage reference terminals on that alternator's regulator ? Did you connect anything to them?
Is here a high current switched terminal that is live only when the ignition switch is in the run position ?
Did you wire a voltmeter or ammeter into the circuit ?
no excite or v ref term, black plug in opening where they would be on a 3 wire. no ammeter, just an idiot light. not aware of a high current switched terminal. Using my volt/ohm meter, I show 12.5 v on battery with switch off. Voltage on Batt with the engine running I get 13.8 or so. Will disconnect from alt and see if there is any current flow from system to alt with switch off. I have milli-amp and 20 amp capabilities on my meter.
Michigan Iron
Member
- Location
- Columbus, Michigan, USA
I too wonder if you maybe have a three wire instead of a one? Personally, I always like the remote voltage sense ability on a three wire and that it starts charging at a lower rpm (no need to increase RPMs to excite it like a one wire).
Outside of that, I would agree that the alternator is bad
Outside of that, I would agree that the alternator is bad
buickanddeere
Well-known Member
Then what switch energizes what terminal when the ignition switch is turned from off to run ?
Sam Womer (PA)
Member
When I put the 1 wire alternator on the John Deere LA I ran the single wire from the alternator to the ammeter then to the battery. I did put a 2"
pulley on the alternator to make it run a little bit faster, it starts charging just a little bit above idle speed. After that it charges even at idle. It has
never discharged the battery . HTH . Sam Womer (PA)
pulley on the alternator to make it run a little bit faster, it starts charging just a little bit above idle speed. After that it charges even at idle. It has
never discharged the battery . HTH . Sam Womer (PA)
Newer one wire alt start charging at a lower rpm than they used to. Just installed a high amp on my dodge pu to replace a motorola.
was supposed to be a three wire but found out it had a one wire regulator in it. Just also put a 10si in my jd1520 need to put on a
wider pulley but other than that just wired it to the batt cable on the starter. works great.
was supposed to be a three wire but found out it had a one wire regulator in it. Just also put a 10si in my jd1520 need to put on a
wider pulley but other than that just wired it to the batt cable on the starter. works great.
Buick, from what I understand with the concept of one wire, it just senses when the battery voltage is low, and will start charging when it senses that condition, and the rpm's are sufficient to activate it. as long as there is some voltage in the battery it is trying to charge. I have driven a one wire off a small Briggs to charge weak batteries in the field, and always went from the output terminal to the pos term on the batt, and it worked fine, with the exception of once when the Briggs burst into flames from a leaky carb gasket. That was fun.....
Ted in NE-OH
Well-known Member
Bad diode in alternator
BarnyardEngineering
Well-known Member
- Location
- Rochester, NY
I agree. The alternator is bad. Can you exchange it?
Frankly I've heard more of these types of problems with one-wires than not... I use three-wire alternators because the wiring is only slightly more involved, and they work 100%.
Frankly I've heard more of these types of problems with one-wires than not... I use three-wire alternators because the wiring is only slightly more involved, and they work 100%.
Steve@Advance
Well-known Member
Try disconnecting the alternator to see if the drain goes away. If it does, the alternator has a bad diode or defective regulator. I would do that first, just to be sure before taking the alt back. How is the health of the battery? If it has a weak cell, it will discharge siting overnight.
Any accessory left on will do the same, so will corroded wires inside a harness or behind the fuse block connection. If you put an incandescent test light in series with a battery cable and the battery post, that will tell if there is a drain. A full bright light is a significant drain. A very dim light is normal for a one wire alt. Though it is a drain, it would take months to discharge a battery.
Any accessory left on will do the same, so will corroded wires inside a harness or behind the fuse block connection. If you put an incandescent test light in series with a battery cable and the battery post, that will tell if there is a drain. A full bright light is a significant drain. A very dim light is normal for a one wire alt. Though it is a drain, it would take months to discharge a battery.
Are any of the old generator regulator wires shorted together, or did you tape each one up individually? None should be connected together, all taped up individually.
You got good advice to disconnect the heavy wire from the alt output stud, then see if the battery stays up.
If the discharge stops with the disconnected alternator, a bad alt diode is likely.
Does your 63 Ford have a charge light or an ammeter ? If it has a charge light, you can make it function with the one wire Delco alternator. You need an alternator harness repair plug from your auto parts store, most any GM from 74-85. Find the small gen light wire at the original generator regulator harness. When grounded with the ign on, it will make the gen light glow. Connect that wire to the small white #1 wire in your new Delco plug. Doing this will not only give you a functioning gen light, but also will make your 1 wire alternator start charging a lower rpm.
You may as well also put a ring terminal on the heavy red #2 wire in the alt plug and add it to the bat output stud. Doing so will cause no problems with the 1 wire alternator and your truck will now be wired to work with a standard 3 wire Delco alternator, should you ever need to replace it.
You got good advice to disconnect the heavy wire from the alt output stud, then see if the battery stays up.
If the discharge stops with the disconnected alternator, a bad alt diode is likely.
Does your 63 Ford have a charge light or an ammeter ? If it has a charge light, you can make it function with the one wire Delco alternator. You need an alternator harness repair plug from your auto parts store, most any GM from 74-85. Find the small gen light wire at the original generator regulator harness. When grounded with the ign on, it will make the gen light glow. Connect that wire to the small white #1 wire in your new Delco plug. Doing this will not only give you a functioning gen light, but also will make your 1 wire alternator start charging a lower rpm.
You may as well also put a ring terminal on the heavy red #2 wire in the alt plug and add it to the bat output stud. Doing so will cause no problems with the 1 wire alternator and your truck will now be wired to work with a standard 3 wire Delco alternator, should you ever need to replace it.
"A very dim light is normal for a one wire alt." Not really with MOST 1 wire regulators made for the SI series Delco alternators built in the last 20 years. The old genuine Delco "red cap" 1 wire alternator had an extra internal wire added from the bat stud to a screw terminal on the "red cap " regulator to keep it energized all the time, and would slowly discharge the battery over time. I have not seen one of those for at least 20-30 years. Almost all the 1 wire regulators built for the Delco SI series alternators in the last 20 or so years, no longer have that connection to battery voltage, they depend only on residual magnetism in the rotor poles to excite themselves, and have no more battery drain than any conventional 3 wire Delco alternator. So today, with rare exceptions, the 3 wire Delco alternator does NOT drain the battery any faster than the 3 wire version.
Steve@Advance
Well-known Member
You're probably right, I haven't checked a one wire in a long time. I was just basing the "very faint glow" on a typical drain test, especially with the later models with the electronics and memory. The old models shouldn't have enough drain to cause any glow unless it has a newer radio or some electronic accessories.
If you suspect a 1 wire alternator is a leaker, an easy way to identify it is to connect a meter between the Bat wire and the bat stud on the alternator to see how much flows into it. Normal for a 3 wire or "good" type 1 wire is only about 1-4 Ma tops. Much more and a guy can suspect either a leaky diode in the rectifier assy or some hack job 1 wire conversion that draws excite power all the time.
Similar threads
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.
Copyright © 1997-2024 Yesterday's Tractor Co.
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy