1969 dart alternator problems

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dallas ward

dallas ward

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i have a 1969 dart . i think the alternator is stock . the car has a new blue holley electric fuel pump on it and is wired in properly. i dont think the alternator is putting out enough amps to run it at a low idle , i have to idle car high to give the pump more amps so it will not stall at idle . what is the stock amps and what size alt can i get in a bolt in package as i dont want to mod any brackets .any help would be helpful
 
Everybody loves to trash these old alternators because they "don't put out at idle."

But I have found that in many cases there is a MULTITUDE of problems.

You may (PROBABLY) have some connection problems in the bulkhead connector. These were marginal in design "back then" and have not improved with age.

Google up the Mad Electrical bypass, whether you do this or not, at least read ab out the problems:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml
from this page here:
http://www.madelectrical.com/electrical-tech.shtml

The other question is, "where did you hook up the pump?" Have you checked how much voltage it is getting? Have you checked the "voltage drop" it is suffering?

In my own case, before doing a partial re-wire on my own 67, it was suffereing a ONE VOLT DROP in the ignition circuit. In a 12-14V system, one volt is a LOT of drop.
 
so i have the battery in trunk it has o gauge to it and it has about 12.5 volts , at the coil it has 10 . 5 way more than just a half a volt drop . im now having problem with spark plugs running rich or dark looking , im thinking it
has to do with poor spark because i just had a carb built by pro fuel systems and changed plugs and the plugs are carboned up after a couple of days . i also just put a new mh electronic ignition conversion in a month or two ago .should i fix power connection at firewall / bulk head to get more volts to coil
 
Under what conditions did you measure this voltage?

If you measured 10.5 "at the coil" and you are using an ignition system with a ballast resistor, that could be perfectly normal

We need more info

What are you using for an ignition?

Did you measure the battery voltage running? At what RPM?

In addition to the running voltage at the battery, you also need to measure voltage, running and charging, at the starter relay "big stud."

How 'bout the battery condition? Has the car been sitting? Battery could be going bad, or just needs charged.

Lots of variables here.
 
it has a stock eletronic ignition system for 1970 and up with four post resistor . didnt check batt running or at big stud but i will . batt is 2 months old
 
when i put the mh wiring harness on it said i had to use all ignition parts from a 1970 and up car with electronic ignition , alt , dist , 4 post ballast , and i used the orange mopar performance parts control unit module for electronic ignition . the problems from 1st post are fixed this is my new one
 
67Dart273 said:
Under what conditions did you measure this voltage?

If you measured 10.5 "at the coil" and you are using an ignition system with a ballast resistor, that could be perfectly normal

We need more info

What are you using for an ignition?

Did you measure the battery voltage running? At what RPM?

In addition to the running voltage at the battery, you also need to measure voltage, running and charging, at the starter relay "big stud."

How 'bout the battery condition? Has the car been sitting? Battery could be going bad, or just needs charged.

Lots of variables here.
Click to expand...
what should batt voltage be running , and what rpm should i be at . what should i have at big stud ,running and charging . my volt meter in car says around 15 volts
 
Install a '70 up alternator and ground one of the "field" lugs to the alternator case then hook up the other lug as normal, you will see a significant difference at idle. The problem your experiencing is due to a higher than OEM amperage load due to the added and more modern electronics that have been added, "70 and up alternators have a higher out put than the '69 and older units. David
 
my machinist said to get good dist because plugs on drivers side are carboned up and the pass side are looking good ..
 
sorry , all of the plugs on driv side are black from carbon , not oil . i lost a plug on driv side from so much black carbon, all plugs on pass side are fine like coffee and cream . my machinist said get good dist because the problem is all on one side
 
Unless he actually checked this out with a scope or some other means, he may be guessing.
 
bohica2xo said:
I think your machinist is smoking crack.

Carbon fouling one bank is a carburetor issue. Which intake manifold and carburetor are you running?

.
Click to expand...
its a new 750 hp carb just done by pro fuel systems , the manifold is a performer rpm air gap
 
Grab your flashlight, and start the engine. With the engine idling, look down the primary bores on both banks. I bet the rich bank is drooling fuel from the booster.

As for upgrading the alternator, do you have one belt on the alternator or two?

.
 
I had similar problems with my 69 Dart. With the battery in the trunk, holley blue electric pump and relay, electric fan and relay, tach and MSD ignition, you will almost need to bypass the bulkhead connector. you also need to go over every and all connections and double check connections and grounds. That is just to much load for those old systems. I have a new powermaster (i think 70 amp) alternator, and when youd start the car it would just go to full charge because it was getting a weak voltage signal at the regulator. I kept the bulkhead connector hooked up, but also ran a bypass wire directly to the starter solenoid battery connection. that took care of my problem. With varying voltage at your fuel pump, your pressure has to be all over the place!
 
bohica2xo said:
Grab your flashlight, and start the engine. With the engine idling, look down the primary bores on both banks. I bet the rich bank is drooling fuel from the booster.
As for upgrading the alternator, do you have one belt on the alternator or two?
what makes it leak fuel from the booster and how do i stop it
Click to expand...
 
Dallas Ward:
what should batt voltage be running , and what rpm should i be at . what should i have at big stud ,running and charging . my volt meter in car says around 15 volts
Click to expand...


First, I think you are experiencing a voltage drop in ignition circuit that voltage regulator is reading, that caused alternator to charge battery at 15 volts. By that, the” ING” post on regulator is connected to ignition circuit that is showing low voltage for one or more reasons.

Is the fuel pump, electric choke, radiator fan, or other high use device feed from ignition circuit? If so, these are causing a voltage drop. Also corroded bulkhead connections, old worn switches with high internal resistance, and bad wire full of bad splices also can contribute to voltage drop, as well as corroded battery terminal, and grounding conductor to block connections.

Any and all additions to ignition circuit should be powered by relays, using the ignition circuit as the trigger, and battery or power post on alternator to feed the load. This will eliminate any parallel paths to ground, and greatly reduce current load on under sized conductors in ignition circuit, which will lessen voltage drop in that circuit.

Normal charging voltage should be 13.8 to 14.5 volts. Any higher and the battery will be over charging, and its electrolyte boiled dry over time… A battery killer.

Having battery in trunk can cause voltage drop as well just because it is so far away from alternator, and loads. Low voltage (12v) dose not travel distances well unless conductor size has been increased to compensate for losses. Conductor sizing can be calculated for any length, and load to lessen voltage drop.

What you need to do is clean up all ignition circuit connections, eliminate any heavy loads from ignition circuit utilizing relays. Check and clean all battery terminals, remove splices by running a new wire, and clean grounding conductor connections to block and chassis.
 
wjajr said:
Dallas Ward:



First, I think you are experiencing a voltage drop in ignition circuit that voltage regulator is reading, that caused alternator to charge battery at 15 volts. By that, the” ING” post on regulator is connected to ignition circuit that is showing low voltage for one or more reasons.

Is the fuel pump, electric choke, radiator fan, or other high use device feed from ignition circuit? If so, these are causing a voltage drop. Also corroded bulkhead connections, old worn switches with high internal resistance, and bad wire full of bad splices also can contribute to voltage drop, as well as corroded battery terminal, and grounding conductor to block connections.

Any and all additions to ignition circuit should be powered by relays, using the ignition circuit as the trigger, and battery or power post on alternator to feed the load. This will eliminate any parallel paths to ground, and greatly reduce current load on under sized conductors in ignition circuit, which will lessen voltage drop in that circuit.

Normal charging voltage should be 13.8 to 14.5 volts. Any higher and the battery will be over charging, and its electrolyte boiled dry over time… A battery killer.

Having battery in trunk can cause voltage drop as well just because it is so far away from alternator, and loads. Low voltage (12v) dose not travel distances well unless conductor size has been increased to compensate for losses. Conductor sizing can be calculated for any length, and load to lessen voltage drop.

What you need to do is clean up all ignition circuit connections, eliminate any heavy loads from ignition circuit utilizing relays. Check and clean all battery terminals, remove splices by running a new wire, and clean grounding conductor connections to block and chassis.
Click to expand...
the fuel pump is on ignition but is wired with relay as per holleys instructions and the pump is all i really have thats constant and i dont have a stereo or stuff like that . the batt has 0 ga wire and all the work has just been done , ive done the grounds over . it has a new mh engine and light harness with all the parts they said to use . when i had the bulk head apart i seen where a wire was hot , probably the power should i bypass
 
when i had the bulk head apart i seen where a wire was hot , probably the power should i bypass
Click to expand...



Heat = bad connection = voltage drop. You need to clean, or replace the brass connectors to eliminate this added resistance. Chances are good that other connections in your bulkhead connector are deteriorating as well. This is normal Chrysler wire harness aging, and causes all sorts of electrical problems.

You don’t have to bypass this connection, just clean it by removing the white or green corrosion, and apply some dielectric grease. Or if you have the ability to change out the male & female brass with new replacements that would be best.
 
the other connections dont look all that bad or green / white , just the one that looks like it got a little hot , plastic looks a little melted. what are the colors on the 2 power wires that go through the bulk head ,so i can see if its the one that got hot . where would i get the correct brass connectors to replace the ones to power in the bulk head . the connectors on engine side are new cause its a new harness from mh wire harness so i just need the brass connector from the inside of bulk head connector . if i cant get brass connectors could i jump in before and after the connector with a new wire
 
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