|07-05-2018 03:56 PM|
|36 sedan||JMHO, do yourself a favor and run a #4 ground wire to the alternator from your bell housing or wherever your ground junction on the motor is, you really don't want all that current flowing back to the alternator through your motor parts.|
|07-05-2018 10:46 AM|
Thank you all for your help. After trying everything and no results I thought it had to be the alt. wire itself. I contacted the harness manufacturer and they told me the harness wasn't made for a 100 amp alt. If you run a high output alt. you have to run a 4 Gauge wire from the alt. to the starter . I did that and it works just fine. With everything on cooling fan, A/C, lights, blower on high and radio it only drops to 13.5 to 13.8 .
|06-22-2018 05:09 PM|
In my case I'm running a 120 amp alternator. It just doesn't put out when it warms up, the battery is in great shape so in traffic just running the ignition it is hard to see if the alternator is producing anything because the ignition just isn't a big drain.
But turn the fans on and you can see the discharge rate start to pull the battery down. And that is a drop that can be seen as staying there when the fans are shut off, not all of it but enough to see on the gauge.
|06-20-2018 02:29 PM|
|'49 Ford Coupe||For what it's worth, my 35 amp output alternator could not keep up with electric fans, A/C, power amp, and headlights, fresh air fan, etc.,, so after some research I got a chrome Proform 100 amp single wire (comes with a factory output test chart) from Advance Auto Parts and, BOOM, all electrical problems disappeared. Instant charging from the moment of startup, stable output. Just my two cents.|
|06-20-2018 01:31 PM|
Currently, this being summer, when I get off the super slab to go into the big city I have to turn the cooling fans on. When that happens the voltage just slips away with no regard for engine RPM. But they only need to run for 15 to 20 minutes not all the time like the winter electrical loads.
Once the engine cools with a gauge reading of less than 195 the alternator is putting out 14.5 following start up. That lasts till the temp gauge hits 195 then back to no output regardless of RPM. This cycle just repeats through the day. The battery is obviously in good shape as for the few minutes it gets a full charge rate it keeps up with the demand of cranking the engine as needed without having to connect it to a charger. But that won't last forever.
This is the second or third GM one wire that has died in this exact same way in about as many years. So I expect that there is some generic fault in these things, perhaps given the mileage I put on in a year they just wear out in this time frame. I'm not researching this any deeper than an afternoon R&R job; but I am going back to the older three wire configuration simply because my history with those is they lasted longer. But as time and the industry mantra of "faster, better, cheaper" (with emphasis on faster and cheaper so 2 outta 3 ain't bad) continues it just might be that anything today just doesn't hold up to my expectations.
|06-20-2018 11:44 AM|
i too am a fan of the 1 wire alternator and suggest you keep a spare diode pack and regulator on hand
buy the good diode pack, i forget what the nomenclature is but it's made for the 100-140 apm alt
i believe eod guy helped me out when i went thru 2 oreillys rebuilds in as many weeks
i now keep spares with me on long runs, i can replace parts in a few minutes
|06-20-2018 07:16 AM|
Think of the exciter wire as the pressure regulator on a compressor. It's job is to recover the air that has been used, before it is all gone. That's the best analogy, and describes what's happening. In spite of what some think the car runs off the battery, not the alt.
Also tells you why a car with one wire willie, has the dim lights. Again using the air compressor as the comparison. Compressor will run continuously if the demand is high. Pump get hot, tool has less torque, performance is degraded.
Same deal happening, as the alt tries to recover the battery loss. And because AMPs are HEAT ...... well 2+2 = hot alt. With solid state devices shutting down, if not going offline completely, out put is degraded .
|06-19-2018 04:12 PM|
I thought it was something new.....
You can make just about any three wire into a one wire by hooking in a jumper wire (I've never had to use a diode). In a true one wire this is done internally.
Once a one wire receives enough output from the charge lug to excite the field it will start putting out juice and to my knowledge will continue to produce juice until the alt stops spinning. The difference is...… you need higher RPMs initially to get the alt to start producing juice, once it starts producing it works about the same as a three wire.
IMO the drawback is...…. the sense wire is taking the reading from the charge lug, which isn't the ideal place to get a sense of the demand/draw on the electrical system. The three wire OEM setup allows the sense wire gets it's reading further down the line and a truer demand/draw on the electrical system.
Both work just fine.
|06-19-2018 01:09 PM|
|JeffB28||Guess we are digging up "old bones" again. https://www.hotrodders.com/forum/one-...or-272721.html|
|06-19-2018 12:32 PM|
|06-18-2018 04:26 PM|
Please explain how "adding a simple diode to your one wire alternator it will excite early and full charge at low RPM's"
Very curious as how that would happen.
|06-18-2018 02:04 PM|
|JeffB28||By adding a simple diode to your one wire alternator it will excite early and full charge at low RPM's.|
|06-18-2018 07:42 AM|
I have had a one wire alternator on this rig for 20 years with no problems.
head lights, plow lights, amber flashing, beacon light, heater and radio
|06-18-2018 07:20 AM|
That is exactly what the problem is with the one wire set up. I say it a thousand times. One wire is for lawn mowers, tractors and gas powered welder type of operational conditions.
It is easily seen when a car is using the one wire deal. When looking at a line of cars stopped, the car with the dim & yellow head lights is the 1 wire set up. Three wire has the same intensity no matter what the RPM.
I not going to bother explaining the why, cause it has been over and over and over.
You will never have the problem with the 3 wire set up....... you're certainly free to ignore the advise.
|06-18-2018 03:12 AM|
|JeffB28||Sometimes guys use too light a gauge feed wire I've always used a 6 gauge battery cable from the alternator to the positive battery terminal and never had issues even with A/C,electric fan and electric fuel pump, check out this article: https://www.tuffstuffperformance.com...structions.pdf|
|This thread has more than 15 replies. Click here to review the whole thread.|