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Alternator conversion from factory to one wire

multimopes

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I know I have seen it on here several times, but, I have 2 electric cooling fans that pull 30 amps each and 40 amps each when starting. I bought a 130 amp American made alternator which was advertised to be able to handle that at idle. Well, it doesn't. I have to raise the RPMs to about 1350 for it to be able to handle the load. There is no smaller pulley available than I have and I am considering changing to an internally regulated one wire alternator system. I was wondering what drawbacks there are to running a one wire versus conventional and what drawbacks there are. Also, would need to know the best way to jump around the voltage regulator and such. By the way, my battery is in the trunk! I read something about this way long ago and somewhere. Damn, I hate electrical ****! Any help would be greatly appreciated.
 
I run a 1 wire alternator. I'm using a 6 gauge wire from the alternator back to the battery disconnect switch. The bigger the cable the better. For power and ground cable I'm using 1 gauge.
 
I know I have seen it on here several times, but, I have 2 electric cooling fans that pull 30 amps each and 40 amps each when starting. I bought a 130 amp American made alternator which was advertised to be able to handle that at idle. Well, it doesn't. I have to raise the RPMs to about 1350 for it to be able to handle the load. There is no smaller pulley available than I have and I am considering changing to an internally regulated one wire alternator system. I was wondering what drawbacks there are to running a one wire versus conventional and what drawbacks there are. Also, would need to know the best way to jump around the voltage regulator and such. By the way, my battery is in the trunk! I read something about this way long ago and somewhere. Damn, I hate electrical ****! Any help would be greatly appreciated.
Why do you think the alternator is keeping up? How low is your voltage dropping at idle with the fans running?

I have a 100A single wire alternator and I have a lo of power drain - dual SPAL fans, Dakota cluster, power windows, Classic Air AC etc etc. At idle my voltage drops from 14V to 12.4V.
 
Voltage drops to around 10.6. If I step on the gas a little come up to 13.7 or so. God forbid it was at night with lights on and/or wipers or heater fan. I used to have less powerful SPAL fans, but they were barely able to keep the temps in range. I had a 95 amp Powermaster alternator with them. The car was previously a bracket racer stripped of all creature comforts. Had a 22" radiator with a single unshrouded electric fan. No good for cruising or much else besides the track.
 
Why did you go with electric instead of a factory fan and shroud?
Is there ever an electric fan setup that moves more air than a 7 blade fan?
 
Why did you go with electric instead of a factory fan and shroud?
Is there ever an electric fan setup that moves more air than a 7 blade fan?
Car was that way when I got it, butchered for drag racing only. I'd love to go back to stock mechanical fan with or without a clutch. The radiator is from Speedcooling and is 2 1" rows. I had to use their shroud setup. Doesn't appear to much room between radiator & fans. I wish I had a stock fan setup to measure from. I am too damn old to drag race anymore and will be replacing the 3.91 sure grip with 3.23's and putting a Bergman Borgesen setup on it. Some kind of small heater would be nice if only to be able to defog the windows if it rains. I also have my eye on a set of reclining bucket seats with side bolsters from Summit, but that will be tight as well due to the six point roll cage!
 
I'm wondering if some diode gone on alt could be a reason for that. What you describe is a very tipical symptom of that. Or some stator winding.

Now, if internal or external reg... I can't see a HUGE advantage on this, aside some of the wirining clean off. External makes it easier to service and still full field the alt if reg fails. At the end depends of the total performance of the setup.

Dunno which alt exactly you have thought
 
Okay you put on a 130 Amp but didn't up the wiring size big problem. Second are the fans on all the time or ran by temp sensor?. Have you had the new alt checked out to make sure it's okay. Or you could take all that off and go back to factory stuff. Have you full fielded the 130 Amp to make sure it puts out that at idle or does it only run higher amps as you increase rpms. My first thing is check all wiring and go bigger on that before anything else.
 
My BB Dart, drive to the track racer, trunk battery, electric water pump, electric fan cooled (manually controlled switched), good battery, and Toyota 1 wire internal reg alt. Keeps up and shows 14v on the Autometer gauge @ 800 rpm idle in gear.

Thoughts on yours'.... regulator issues, wire size as others mentioned (put your hands on the supply wires to see if they feel warm), battery ampacity, and you mentioned 30/40 amp fans, mine too, but that is just a fuse/start-up rating, and should pull a lot less after initial surge start and up and running. Below is the alt I use, and I'm really happy with the internal reg 1 wire set up.

 
Voltage drops to around 10.6. If I step on the gas a little come up to 13.7 or so. God forbid it was at night with lights on and/or wipers or heater fan. I used to have less powerful SPAL fans, but they were barely able to keep the temps in range. I had a 95 amp Powermaster alternator with them. The car was previously a bracket racer stripped of all creature comforts. Had a 22" radiator with a single unshrouded electric fan. No good for cruising or much else besides the track.
I have the 95A Powermaster and it handles your load and more. There must be something else. What's the health of the battery like? As Nacho said could be the VR.
 
Thank you all for the responses. The fan power comes direct from the alternator and is fused. The alternator does just fine with anything & everything except when those fans kick on. I have a Derale solid state fan controller that is malfunctioning. Factory says it went bad. The entire wiring of the car is suspect due to age (50 years old) and being gutted for racing. Let's put it this way. When I got it, there were wires run through freshly drilled holes in the firewall, without grommets to isolate a possible short. I fixed those. I went through everything I can see but there may be issues in places and disconnected stuff behind the dash which is extremely hard to access with the roll bars coming down on each side of the front seats, and a custom made panel from the center of the dash to the floor hump for a radio & aftermarket SunPro gauges. Except for the fuel gauge, the rest of the factory gauges are disconnected. No issue with a bulkhead connection to the amp gauge or anything. Even with seats removed it's a bitch. As stated, the battery is in the trunk with heavy gauge wires running to starter & engine ground. They put a kill switch through the rear bumper which may have been mandated by whatever class the car was raced in; however..............The kill switch doesn't shut off the engine like it's supposed to because it only kills the battery, the alternator keeps the engine running just fine! I use the kill switch as an alternator test switch which it does very well. I have added at least a half dozen grounds all over the car and sanded to bare metal everywhere to make sure the ground system works. I did put manual override switches to the electric cooling fans as a backup due to unreliable fan controllers. I keep an eye on the engine temp like a hawk. I have a different adjustable fan controller to install but lately I'm fed up with this electrical crap. I think I am going to try to find a shroud for a factory mechanical fan. Most problems with any newer car today is usually associated with electrical stuff. Too damn many computer controlled things. My older brother was an electrical engineer, so when I had a question about something I 'd ask him. Unfortunately, he doesn't live around the corner. I spoke with Summit Racing the other day and there are more powerful alternators available both internally & externally regulated. By the way, the battery was an Optima Red top for about 10 years, replaced last year with a Diehard Gold. I have also changed out the voltage regulator 2 or 3 times as well for purposes of trouble shooting, one was bad. No changes with any functionality on anything else.
Second are the fans on all the time or ran by temp sensor
The fans are run by a temperature sensor / or when I get fed up and flip on a manual power switch which I have for each fan.
 
Do yourself a favor and breakdown each section and easier to troubleshoot. Amp rate with battery. What is the Amp draw with the fans?. Start with fans maybe full pull on amps but should drop after that as stated above. Small things first and go from there.
 
Thank You for the suggestions. I will dive into it as soon as the cold weather breaks which is just around the corner.
 
Where is the power for the accessories drawing from?

That can be a BIG deal especially when you have a run from front to back to front again, charging system and starter relay area distribution point.

If you have an aftermarket style alternator, there should be a slope chart with it or at least available. The dead output at idle is classic mopar alternator territory.
 
Why did you go with electric instead of a factory fan and shroud?
Is there ever an electric fan setup that moves more air than a 7 blade fan?
Every time this subject is discussed, the only reference to the electric fans is the number used and the amps consumed per fan. The most important number is not amps or whether the fan is pushing air thru the radiator or pulling air thru the radiator.....but NEVER THE VOLUME DELIVERED in Cubic Feet per Minute (CFM) at a specific static pressure (S.P.) in inches of water column or at a specified unit of measurement, such as pounds per hour. These aftermarket or auxiliary fans are usually a propeller type....the shape of the blades vs a centrifugal blade design. Its a well known fact that propeller fans have a relatively low static pressure capabilities, especially when mounted directly in front of the radiator. NO ONE ever states the installed fan's CFM and S.P. rating....why....because the supplier does not say or offer the fan specs....just the horsepower or amps and dollars. ALL fans, when designed, are tested and the air flow developed and static pressure are plotted on a graph. The horsepower at each point is measured and plotted on the same graph.
The worst application is when the fan is on the hot side or engine side, of the radiator. The fans CFM rating is reduced because of the density of the air being handled, or pounds per hour of air, is reduced because of the hot air temperature being handled. The closer the fan is to the radiator, the higher the static pressure the fan has to work against, reducing the overall CFM rating produced by the fan. These are fundamental aspects of using fans...called The Fan Laws and apply to all fans, with the most critical aspect being impeller design. All, or almost all, aftermarket suppliers csnnot say what their product is capable of or produce a fan curve of the fan they are offering for YOU the purchaser is buying. The average purchaser will say...."I don't know anything about fans" and rely on the vendor (or your buddy)...so learn about the fan, ideally from the manufacturer....but unless you state your requirements, including air temperatures being handled and volumes needed, and mounting location, the vendor can ONLY guess what is being proposed will function correctly. A fan curve is a necessary document in making an appropriate selection.....just my opinion of course, having specified and purchased all types of fans and air moving devices for industrial applications....from 1/4 HP room ventilator thru 2000 HP process air supply fan in a chemical plant.
BOB RENTON

1680657584384.png

Typical propeller fan curve with horsepower shown...
 
With the fans shut off is your alternator working correctly ?
If it is I would sure consider removing the electric fans and installing a 7 blade mechanical 18" fan and spacer like Kerndog posted.
That and a shroud should move enough air to cool .
 
No no no! I’ve done been through this! You have to upgrade the voltage regulator also to match that 130 amp alternator. Also if others haven’t mentioned it you need to ground the alternator itself and run a 4 gauge wire from the alternator stud to the battery positive post or starter relay. Problem solved!!! Tuff Stuff helped me solve my problem. The guy I talked to there was very Mopar knowledgeable. Don’t use a 1 wire. A 3 wire is better and don’t believe the crap about electric fans if did correctly. When I was doing my remote tuning with Fastman he said holy **** what E-Fan and cooling set up are you using? I said why? He claims he has never seen a BBM cool down that fast the way my motor was built.
If this isn’t the style regulator you have I might have a part number for the other one but if not you may just be able to Google it, they have the upgraded square style also.

5659621F-4A4D-4E29-B94A-3228E614092B.png
 
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Thank you all for the responses. The fan power comes direct from the alternator and is fused. The alternator does just fine with anything & everything except when those fans kick on. I have a Derale solid state fan controller that is malfunctioning. Factory says it went bad. The entire wiring of the car is suspect due to age (50 years old) and being gutted for racing. Let's put it this way. When I got it, there were wires run through freshly drilled holes in the firewall, without grommets to isolate a possible short. I fixed those. I went through everything I can see but there may be issues in places and disconnected stuff behind the dash which is extremely hard to access with the roll bars coming down on each side of the front seats, and a custom made panel from the center of the dash to the floor hump for a radio & aftermarket SunPro gauges. Except for the fuel gauge, the rest of the factory gauges are disconnected. No issue with a bulkhead connection to the amp gauge or anything. Even with seats removed it's a bitch. As stated, the battery is in the trunk with heavy gauge wires running to starter & engine ground. They put a kill switch through the rear bumper which may have been mandated by whatever class the car was raced in; however..............The kill switch doesn't shut off the engine like it's supposed to because it only kills the battery, the alternator keeps the engine running just fine! I use the kill switch as an alternator test switch which it does very well. I have added at least a half dozen grounds all over the car and sanded to bare metal everywhere to make sure the ground system works. I did put manual override switches to the electric cooling fans as a backup due to unreliable fan controllers. I keep an eye on the engine temp like a hawk. I have a different adjustable fan controller to install but lately I'm fed up with this electrical crap. I think I am going to try to find a shroud for a factory mechanical fan. Most problems with any newer car today is usually associated with electrical stuff. Too damn many computer controlled things. My older brother was an electrical engineer, so when I had a question about something I 'd ask him. Unfortunately, he doesn't live around the corner. I spoke with Summit Racing the other day and there are more powerful alternators available both internally & externally regulated. By the way, the battery was an Optima Red top for about 10 years, replaced last year with a Diehard Gold. I have also changed out the voltage regulator 2 or 3 times as well for purposes of trouble shooting, one was bad. No changes with any functionality on anything else.

The fans are run by a temperature sensor / or when I get fed up and flip on a manual power switch which I have for each fan.
You also said it was fused? You do not have relays on your E-Fans? I have 2 fans which both go to 30 or 40 amp relays, can’t remember, and then the hots are fused and I wired them straight to the battery.
 
Why do you think the alternator is keeping up? How low is your voltage dropping at idle with the fans running?

I have a 100A single wire alternator and I have a lo of power drain - dual SPAL fans, Dakota cluster, power windows, Classic Air AC etc etc. At idle my voltage drops from 14V to 12.4V.
You should still have more Volts than that when charging correctly.
 
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