New 1 Wire Alternator wouldn't excite I think !

downtownblues

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Hi Guys . Recently i've installed an CVF Racing Beast Serpentine Kit on my 66 Monaco 500 /w 440.With there 100 Amp 1 Wire chrome plated Alternator and Saginaw Pump.Also added an Cold Case Aluminium Radiator with dual Fans.I also did the underhood Ammeter Bypass and checked all the connections. I've deactivated the stock Voltage Regulator. The new Alt is internally regulated and self exciting. The Problem is it won't charge.Max 13V when idling. Is it possible that i have to excite the Alt after installing? If yes,did anyone know how to do it the right way.Maybe i have to excite it once, and then it will work. Or what else could be the problem. Bulkhead looks good. Headlights works. After charging the Battery 13.3 at Bat and Alt. Optima Yellow almost new
 

Davea Lux

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Hi Guys . Recently i've installed an CVF Racing Beast Serpentine Kit on my 66 Monaco 500 /w 440.With there 100 Amp 1 Wire chrome plated Alternator and Saginaw Pump.Also added an Cold Case Aluminium Radiator with dual Fans.I also did the underhood Ammeter Bypass and checked all the connections. I've deactivated the stock Voltage Regulator. The new Alt is internally regulated and self exciting. The Problem is it won't charge.Max 13V when idling. Is it possible that i have to excite the Alt after installing? If yes,did anyone know how to do it the right way.Maybe i have to excite it once, and then it will work. Or what else could be the problem. Bulkhead looks good. Headlights works. After charging the Battery 13.3 at Bat and Alt. Optima Yellow almost new

The internal regulator should supply what ever level of charging amps is necessary to maintain the battery charge. If it does not need 100amps you will not get 100 amps. If the battery was in a discharged state and you are not getting any output or very low output, likely you have a defective unit. Take it off and have it tested. Also check the lead going to the alternator to be sure you have good voltage coming in. Put the unit under full load by turning on the lights and heater fan in the high position, that should jump the charge rate, if the charge rate does not change, again, probably a defective unit. You can also try removing the hot lead from the alternator and replace it with a jumper lead directly to the positive battery cable. This bypasses the existing wiring and eliminates it as a source of the no charge situation. You might also want to temporarily install an ammeter in the charging circuit to verify what the output of the alternator is, this is more accurate than voltage readings.

Dave
 

Ross Wooldridge

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As above from @Davea Lux .

Please note however, that your car's wiring was never designed to handle anywhere near 100 amps, so if for some reason your alternator works and gets a request for full output from the regulator, you're going to have a number of carastrophic meltdowns.

My internal Lost in Space robot is shouting "Danger Will Robinson", and waving its arms.
 

CBODY67

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Seems like the police vehicles had an 80-amp alternator on them? Which is not that far off from 100 amps. I suspect that unless there might be some high-power sound system amp or hydraulic pumps, the normal max load would not be but 50 amps (considering the size of the normal factory a/c alternator, back then)?

The '78 or so Cordobas had a 100amp alternator when they got the heated rear window, so obviously, that curcuit had to be upgraded to handle that load, but not the complete wiring harness itself (unless somebody planned ahead in the original harness configuration/specs when the cars were approved for production). Same for the '74 "formal" cars, too?

End result, some concerns might not be "concerns" if everything is still stock in the vehicle equipment, but the same "non-concerns" can quickly become "major concerns" IF some wires short each other. Might be a good idea to inspect, clean, and "re-lube/seal" the bulkhead connector parts?

Proceed at your own risk . . .
CBODY67
 

Mr C

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Seems like the police vehicles had an 80-amp alternator on them? Which is not that far off from 100 amps. I suspect that unless there might be some high-power sound system amp or hydraulic pumps, the normal max load would not be but 50 amps (considering the size of the normal factory a/c alternator, back then)?

The '78 or so Cordobas had a 100amp alternator when they got the heated rear window, so obviously, that curcuit had to be upgraded to handle that load, but not the complete wiring harness itself (unless somebody planned ahead in the original harness configuration/specs when the cars were approved for production). Same for the '74 "formal" cars, too?

End result, some concerns might not be "concerns" if everything is still stock in the vehicle equipment, but the same "non-concerns" can quickly become "major concerns" IF some wires short each other. Might be a good idea to inspect, clean, and "re-lube/seal" the bulkhead connector parts?

Proceed at your own risk . . .
CBODY67

The 100 amp alternator (like below) came out in 75 with the arrival of the grid rear defrost. 74s still had 65-ish amp alternators stock, but I've seen a few with the 75 100 amp set up retrofitted with the appropriate bracketry...including one I owned. The harnesses appeared to have been the same. Never had a problem with the 74...66 may be a different story.

MOPAR-100-amp-alternator-3874992-3.jpg
 

Ross Wooldridge

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Highest output alternator in a 66 C body was roughly 65 Amps heavy duty police spec. Leece Neville systems.

Highest regular police/taxi alternator was 59 amps.

Both charging systems in those cars got special factory installed charging system upgrades such as bulkhead bypasses and multiple fusible links offering more protection, installed with firewall mounted terminal blocks etc. Designed to avoid the already known issues with bulkhead spade connectors etc.

AFAIK, regular street cars, even with AC, Power Seat ls etc., got a 35 amp alternator max.

Unless the car in question was spec'd for a taxi/police charging system, that car has likely seen only a 35 amp alternator, or an aftermarket rebuild at around 50 amps.

100 amps is a fire waiting to happen without certain mandatory upgrades and safety retrofits.
 

furious70

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My GM 1 wire needs to be spun 1500rpm or so to energize.
You do need to eliminate the old regulator and the alt needs to be attached to a place in the wiring that will sense the greatest load. Mine is attached to the batt stud on the starter solenoid and my fuel pump, stereo amp, efi ecu, injection pump, etc all attach there as well. Ammeter bypass of course.
 

Davea Lux

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.Another good place to hook the ammeter bypass is to the large lug on the stater. That way you avoid any corrosion issues on the battery terminal. For 100amps about a #6 wire is ideal if you expect the circuit to draw full amperage without heating up. Be sure to use quality connectors.

Dave
 

Gerald Morris

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I advise you to run directly from your charging stud to the battery, around the front of the engine compartment in #6 AWG, using #10 AWG fusible link wire at the battery to make the connection. Use a good quality marine terminal on the battery with a 3/8" stud, and suitable quality ring terminals to that. You can protect the circuits feeding from the battery to the starter relay in a #8 AWG line w #12 AWG fusible link wire with good confidence then, unless you're actually PULLING 100A from some monstrous load in the dash, like a high power audio amplifier. These should have their own dedicated circuit from the battery, using relays if necessary.

The battery acts as a major resistive load itself, from the charging source (your alt) and by making the loop from the alternator go ONLY to the + terminal on the battery, you simplify the charging circuit nicely. Mind you, Kirchoff's Current Law states clearly that the sum of all current into any node MUST come to 0, so make sure your GROUND conductor from the battery ALSO is at least #6, or several jumpers summing to the same ampacity. I use that approach on my ride, and for 4 years have had no trouble. I shouldn't, after replacing the burnt and butchered mess I'd inherited within a month of purchasing the car.....
 

Gerald Morris

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.Another good place to hook the ammeter bypass is to the large lug on the stater. That way you avoid any corrosion issues on the battery terminal. For 100amps about a #6 wire is ideal if you expect the circuit to draw full amperage without heating up. Be sure to use quality connectors.

Dave
#4 AWG would give a better safety margin, but at 12-15VDC, #6 should be OK. Fusible link wire gets rare for larger sizes too, which is my best rationale for using #6 for a 100A circuit in a slabby like his or mine..
 

furious70

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As along as the wiring is big and fresh and connections are excellent that's ok, the potential problem going to the battery is that the alt never senses the full load because of the loss in the circuit from the battery to the consumers and therefore the consumers run at less than full voltage all the time even though the battery is kept charged.
 

Gerald Morris

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Not so. Even with a dedicated loop for charging, system voltages are in parallel and each loop will get the same voltage. (Kirchoff's Voltage Law: sum of the drops on a given loop =0.) What results from this approach is to push charge to the terminal on the battery as the first load. In fact, with a good conductor from the battery to the starter relay, (I use #8 at present) one can treat the starter relay terminal and the battery terminal as a super-node, getting the current from the alternator just as it would if it was run around back through the loop Mopar designed 55+ yrs ago for a 30A system. I removed that one bit of #10 wire between alternator and starter terminal, upgraded the conductors for charging and the dashboard supply to #8, and All is Well!

By moving the charging wire to the front of the compartment, you DO enhance safety a bit, and make it easier to provide extra overcurrent protection, to both charging conductor and the starting terminal each. The older scheme had but the one fusible link, at the starter terminal from the battery. This resulted in an electrical fire about a month after I got the car when the charging stud on the alternator grounded to the fender as a consequence of a broken motor mount. I had PLENTY stuff to repair on that car when I first got it, and still do, though the nature of the repairs has changed considerably since then, unless I find some hidden kluge left lurking under sheetmetal as I recently have.....

Again, upgrade both main power conductors, and protect them both properly! I plan to upgrade from a 60A to 100 or 130A alternator by either Tuff Stuff or PowerMaster this coming year, and will use #6 or even #4 for my mains then.
 

furious70

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You disagreed and then said what I said - 'your supernode' comment is the same.

Old tractors with 1 wire systems and small/old wiring that have extra lights and radios suffer from this arrangement because there is no supernode as you call it, and as I called it, substantial resistance in the circuit leading from charging source to consumer.
 

downtownblues

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Hello again
I have my old Alt tested,replaced both bearings and put it back in the car. I think it has 60Amp,but don't know for sure. Its the newer 3 Wire squareback style,i also have the newer style Voltage Regulator. 6 Gauge Wire with Midi Fuse fom Alt Bat directly to Battery.An additional 8 Gauge Wire with 12 Gauge fusible Link vom Alt Bat to Bat+ Stud on Starter Relay. One Fld Wire to VR Ign blue,and one Fld Wire to VR green.So now the Alt is charging. Voltage shown at Battery is about 15.7 . I think this is too high. So whats the problem now. What have i done wrong. Car has electrical Dual Fans,but AC was removed. Fans,Lights etc works good Sven
 

Mike66Chryslers

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You disagreed and then said what I said - 'your supernode' comment is the same.

Old tractors with 1 wire systems and small/old wiring that have extra lights and radios suffer from this arrangement because there is no supernode as you call it, and as I called it, substantial resistance in the circuit leading from charging source to consumer.
I agree. This is the reason why I always recommend people against ditching the original system with separate VR and switching to a 1-wire alternator. It's simpler but less ideal for automotive use than the original system. As I like to say, 1-wire alternators were designed for tractors, and that's where they belong. :D

The charging system regulates the voltage at whatever point in the system the VR is sensing. This should be at a common power node. In most of our cars that is the big stud on the starter relay. The internal VR in a 1-wire alt only regulates voltage at the power terminal of the alternator itself, so it's not accounting for I2R losses in the wiring. Depending on wiring layout and gauge, this may result in undercharged battery, dim headlights, etc.
 

furious70

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or as the OP is seeing - an overcharge at the battery when the alt is keeping up with the heavy consumers sensed elsewhere.
15.7 is too high. Do you see that voltage delivered to the fans? To the fusebox under the dash?
 
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