More ignition issues on the dart

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^^The above is a pretty good assessment^^

A BIG BIG problem with pickups is likely THE CONNECTOR. There is very very little "no" current through it, and if they get corroded, they can lose the pickup signal
 
Dave999 said:
i think you are on the right track the voltage value you measure when you spin is totally depnedent on how fast you spin

and if, say, half the coil in the pickup has fused togther but the other half is still kinda working you will get a voltage but tiny and too small to trigger your igntion box

there is enoug here to indciate that a new pickup, just for piece of mind, is not money wasted.

and provided your regulator and alternator are all in good condition tha chances of wierd voltage spikes killing it are low

the pickups die from old age vibration humidity and heat normally. its a magnet on a steel holder which has tip near the relcutor star a small coil of hair thin wire that is painted in varnish is hidden in the black bit that sits around the tip. The points of the star moving past the pickup wave the magentic field around as they pass the tip of the magnet and coil holder, you can feel this happening, a moving magnetic field causes a small current in the coil and a volatge between its ends. 1 end of the coil connects to 1 lead on the dizzy the other end of the coil connects to the other... if the varnish on the wire starts to degrade fewer and fewer of the loops of wire in the coil do any good work and you end up with this situation.
or the magnet looses its magnetism and with low magnetism the voltage produced is just too low

vibration and heat kills magnetism, you un magnitise things by heateing them up and repeatedly htting them with a hammer. heat and vibration can have an adverse impact on thin varnished wire.. hence the pickups have a life that is limited to some time period that will have been calculated to be longer than the orginal warranty on the car in question... :)

But someone here will pipe up saying they haven't change the pickup in their dizzy for 50 years..... all i can say is lucky lucky boy...

dave
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How much voltage is required to trip the ignition box?
 
Disagree with some of these comments. There is nothing inside the p/up that is likely to degrade over time. Not sure what the threshold is to trigger the ECU, but it is very low.
It has to be low enough:
- so that enough voltage is generated on a freezing cold winter morning when the cranking speed is low
- in case the air gap is not exactly 0.008" & is slightly larger, which will reduce output voltage slightly.
 
Spinning the dizzy by hand gives me .5v AC, which I traced all the way back to the pigtail that plugs into the IGN box. Spinning it with the starter, however, only gives me .1v AC. Grounding the dizzy wire sparks it but the dizzy pickup doesn’t. Either .1v isn’t enough, or the pigtail is screwed up. All my connectors in the pigtail are nice clean brass except one of the dizzy wires. Tried cleaning with a cotton swab to no avail. I suppose I could try another pigtail, I have extra harnesses
 
67Dart273 said:
I'd say replace the pickup.
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Lol, I just put a new one in. Only thing I can think of is maybe the transistor in my Ign box is fried. Idk. I get a spark when I turn the key and a spark when I turn it back and that’s it. And that happens regardless of wether the dizzy is plugged in or not. I replaced the pigtail. Nothing. I tried another IGN box I had laying around, but that one doesn’t even spark when the key turns, so that one must be totally fried. It’s got a new ballast, new switch, new pickup, new coil, the only thing I haven’t done at this point is replace the ign box
 
When you tested the 'other' box, was it grounded? Has to be grounded to work.
 
Okay, so I tested my used and my new pickup according to the spec this guy gives in his article. 350-550Ω. Both tested low ~250Ω. I pulled the old distributor, which I replaced before any of this happened, and tested its pickup. 375Ω. In range. This pickup also has a higher voltage output. ~.75vAC when spinning by hand. Others took some effort but were able to get up to ~.5vAC. Tomorrow I’ll try this dizzy and see what happens. I’ll be taking that $52 new pickup back to the store.

EB9322E8-1812-401E-9BA8-5890A8F1EFC5.png
 
I have measured Chrys p/ups as low as 140 ohms, worked perfectly in vehicle. My 1972-78 Motors Manual specifies resistance as ok if between 150-900 ohms.
It maybe that different wire thicknesses have been used in the p/ups. Thinner wire will have more resistance.
As for voltage differences, that is affected by airgap, smaller airt gap gives higher voltage.
 
idk anymore man nothings working. the only thing left to do is shell out for another IGN box, which I really don't want to do. I've checked every voltage/resistance spec on everything in the ignition system. I have replaced the coil, ballast, switch, pickup, and even the pigtail that plugs into the IGN box. I cant figure it out. you'd think it would be a simple fix. I drove it to work one day, I got there fine. I go to leave and I started having issues getting it to run after starting, so when I finally got it to start I kept on the gas and double footed it home, then I got home and it died and hasn't started since. Like I said, I've checked everything. I am just at a loss at this point. I would think that maybe something had rattled loose or something like that given the context of how it died, but nope. I'm about ready to just give up at this point. I just don't know what to do anymore.
 
I would do this: the blue wire that goes to the dual bal res. Leave in place but run a jumper from that blue wire to the bat [+] terminal. That bypasses all the wiring, plug/sockets etc. See if it starts & keeps running. Report back. It is just illogical that all these ign boxes, p/ups, bal res etc are faulty.
 
Dave999 said:
stick your meter on AC Volts in the mili volt range that measures the samllets voltages.
put black lead in common and red lead in volts (+) or the red and black sockets (depends on meter)
put 1 probe in the socket on the dizzy wire plug, use a self tapping screw or a wad of aluuminiun foil to hold it in. and 1 probe on the bullet of the distributor wire plug and spin the drive with your hand, doesn't matter which way
or drive it with a drill of eletcric screw driver (although you will need 3 hands to do that)
you should see the meter register some small volatge that gets bigger the faster you go.
if you don't see any meter action you are in the wrong meter range volts or Kvolts OR the pickup is bad.
if you do see some volts measured, check the gap between pickup and the 8 or 6 point iron part that spins, set it correctly , clean up the connector and try again.


other test is continuity test

Do not spin the rotor its not necessary for this test
And you can do this one with the dizzy in the motor. its easier to do.

Just connect both leads together with the meter on the beep or diode setting and test your meter to fimiliarise yourself with the sound of GOOD circuit GOOD continuity which will be a clear beep or a good stong light indicator of continuity, most beep . if its beeps you know you are on the correct setting.

You can now apply the leads to the dizzy pickup one to socket one to bullet, doesn't matter which way and it should beep.
if it doesn't, the coil in the pickup is burned out or snapped

rockauto or similar for a new pickup
make sure you get a v8 one for a v8 or a slant 6 one for a slant six. otherwise you will have to un rivet the pickup from the plate it comes on, and re rivet it onto the one you have, and the wire colours will be wrong.

Dave
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Great way of explaining it ! Not my issue though is Handy to Learn! Thank You!
 
SpriceyStuff said:
idk anymore man nothings working. the only thing left to do is shell out for another IGN box, which I really don't want to do. I've checked every voltage/resistance spec on everything in the ignition system. I have replaced the coil, ballast, switch, pickup, and even the pigtail that plugs into the IGN box. I cant figure it out. you'd think it would be a simple fix. I drove it to work one day, I got there fine. I go to leave and I started having issues getting it to run after starting, so when I finally got it to start I kept on the gas and double footed it home, then I got home and it died and hasn't started since. Like I said, I've checked everything. I am just at a loss at this point. I would think that maybe something had rattled loose or something like that given the context of how it died, but nope. I'm about ready to just give up at this point. I just don't know what to do anymore.
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God Bless Mother Mopar,She Got Ya Home Brother!
 
if you can take your pickup back..by all means do it...but handy to have a spare. Trying tpo help remotely all we can do is suggest things from our own experiance... having had picksups go bad....and i'll guess at the junction between lead wires and the tiny coil....well you can see why they are sometimes the cause.

1 last thing as the whole lot all seems to work in isoltation (obvioulsy can't really test the igntion box)

try undoing, cleaning up with a wire brush and re doing up your engine to chassis earth strap...... couple of spikey washers and some grease on it will see it good for the next 50 years.. :)
this is an area thatb can just go bad usually after a transition from hot dry to cold wet weather or indeed humid to dry.. anything that has an impact on corrosion of the rust (brown) or verdigris (green and white) nature

resistance here will mess with everything.....

if there is a problem and you fix it you starter will spin faster as well...
 
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Dave999 said:
if you can take your pickup back..by all means do it...but handy to have a spare. Trying tpo help remotely all we can do is suggest things from our own experiance... having had picksups go bad....and i'll guess at the junction between lead wires and the tiny coil....well you can see why they are sometimes the cause.

1 last thing as the whole lot all seems to work in isoltation (obvioulsy can't really test the igntion box)

try undoing, cleaning up with a wire brush and re doing up your engine to chassis earth strap...... couple of spikey washers and some grease on it will see it good for the next 50 years.. :)
this is an area thatb can just go bad usually after a transition from hot dry to cold wet weather or indeed humid to dry.. anything that has an impact on corrosion of the rust (brown) or verdigris (green and white) nature

resistance here will mess with everything.....

if there is a problem and you fix it you starter will spin faster as well...
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Thanks. Seeing how I don’t have anything left to check, I’ll do that when I get home. I overlooked the ground because generally in my experience a bad ground causes it to not even turn over. And it still turns over at normal speed. But I’ll recheck the ground both on the block and to the core support. Like I said, I’ve got nothing better to check at this point. Also, I don’t have a tachometer, but that’s a useful tidbit of information to keep in mind. If nothing else, I’ll try and put together a video of everything that it does (and doesn’t do) this weekend when I’m off work cause as it sits even on a day shift there’s only a less-than-half hour period between the end of my shift and sunset.
 
I troubleshot an ignition system on a 77 Dodge truck once. i went by the book, and came up inconclusive. I said the hell with it and threw another box on it and tit fired right up. Think of the most obvious thing and try it the ignition boxes fail it a common occurence.
 
Dartswinger70 said:
I troubleshot an ignition system on a 77 Dodge truck once. i went by the book, and came up inconclusive. I said the hell with it and threw another box on it and tit fired right up. Think of the most obvious thing and try it the ignition boxes fail it a common occurence.
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Yeah. I’m just hesitant to do it cause it’s a 5 pin ign box and they’re not easy to find, and they’re more expensive than 4 pin boxes. Also I read on another thread that they make 4 pin boxes that have 5 physical pins so I don’t know looking at a box if it’s really a 5 pin or a 4 pin. It’s spooky. But since I don’t have anything else (besides the above mention led ground check) I suppose it’s worth a shot. No wires broke so there’s no other reason I can think of for the issue I’m having unless maybe the transistor in the IGN box burned out. I think thats like the main reason they fail isn’t it?
 
There are several transistors & numerous other components inside the 'box'. Any one of them could fail.
 
You don't NEED a 5 pin box. 4 pin will work in place of 5 regardless of whether you have a 2 or 4 pin ballast. But a true 5 pin MUST have a 4 pin ballast

I would SERIOUSLY consider a conversion to a simple 4 pin GM module. They are in effect, a 4 pin box, and many of us use them. I've used these on several conversions, including the now long gone Toyota / Cletrac, "Toyotrac"

Sold it in '13...........

www.forabodiesonly.com

[SOLD] - Sell Toyota powered Cletrac Crawler Dozer

in Coeur d Alene, ID asking 1500.00, trades, etc Fixed this up thinking I was going to move out of town. Ya. Cletrac, what, HG? I bought with junk engine, converted to Toyota 20R, Toy 4 speed drives Cletrac 3 speed. New seat, hydraulic hoses and valve. Needs throttle...
www.forabodiesonly.com www.forabodiesonly.com

_mg_6371cs-jpg.jpg
 
SpriceyStuff said:
Ok so on both the current pickup and the new one I got at the store, the meter does not beep with the continuity test. I get numbers like .2-.3. On another distributor I have laying around, it DOES beep and I get like 0-0.001. I’m not sure how to interpret this information.
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If you are like me, that beep frequency I cannot hear, my younger friend can hear it easily.

Imagine that.

Your hearing could be shot in that range.
 
67Dart273 said:
You don't NEED a 5 pin box. 4 pin will work in place of 5 regardless of whether you have a 2 or 4 pin ballast. But a true 5 pin MUST have a 4 pin ballast

I would SERIOUSLY consider a conversion to a simple 4 pin GM module. They are in effect, a 4 pin box, and many of us use them. I've used these on several conversions, including the now long gone Toyota / Cletrac, "Toyotrac"

Sold it in '13...........

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View attachment 1716010609
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I’d have to look at my diagram. How does a 4 pin work in a 5 pin slot? What it’s being lost when we don’t use the 5th pin? I’ll have to look.
 
This is how you learn about the mopars.

We cut our teeth on the simpler points distributor systems when I was a young man.

You could get them running with one hot wire from the battery, or even a coat hanger if you were out and about.

I now have on hand 5 mopar distributors, points and electronic, big block and small block on hand.

She be running in 5 minutes.

Cut your teeth . . .
 
George Jets said:
This is how you learn about the mopars.

We cut our teeth on the simpler points distributor systems when I was a young man.

You could get them running with one hot wire from the battery, or even a coat hanger if you were out and about.

I now have on hand 5 mopar distributors, points and electronic, big block and small block on hand.

She be running in 5 minutes.

Cut your teeth . . .
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I’m working on it lol. I stockpile everything I can fit in my little apartment. Won’t be long before you can’t get it anymore…
 
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