73 Dart Alternator doesn't show charge anymore.

[SputnikOne]

Agreed on all these points, my work has plenty of stuff I can use for this application, but is that why you think it's not charging the battery?

 

[SputnikOne]

The engine connector doesn't seem very willing to detach, pushing both the tabs on the sides down but it's not budging.

 

[SputnikOne]

Well, I might have a slight idea why the power wire bypassed the connector, it might be just a *little bit* damaged

 

[SputnikOne]

The field wires for the alternator are the two farthest from the damage, everything looks fine there.

 

[SputnikOne]

The connector for the blue wire has two blue wires coming out of it, the old electric fuel pump has a blue wire so I assume that's where it was added on, the pump as a ground wire that came out of it, but was removed with the pump, could the lack of ground on this now unused wire be the issue with the alternator?

 

[SputnikOne]

Yeah, checked with the voltmeter, the old pump wire is coming off the blue wire for the alternator for some reason, should I just connect the spare wire to ground?

 

[Mattax]

My recollection is the shop manual shows some engines got an electric choke assist. That's why its a ? on my drawing.

How are you checking with the voltmeter? Did you reconnect and turn the key on? or do you switch the meter to measure continuity or resistance?

It is certainly possible the line or connection was damaged by the addition power needed for the pump. Or by the poor splice job.

should I just connect the spare wire to ground?

That would be a short to ground and will melt some more wire!

 

[SputnikOne]

I am messing continuity between the pin inside the connector and the end of the spare wire after I removed the electrical tape, I have the battery disconnected right now while I screw with all this stuff.

 

[Mattax]

OK. That's the safest way.

I would remove and clean all of the terminals in that connector.
Look carefully at the condition of the J2F and G. It may have failed right there.

Lemme find the pictures for how to remove and add them to this post.
Depress the side of the male terminals. Then push out the back.

For the females, there are tools for this but filing somehting like a cotter pin flat will work too.

Slip the tool in from the front to depress the tab, then the terminal can be pushed out the back.

 

[SputnikOne]

130 MOhms from the blue pin to the blue connector on the alternator, and the continuity doesn't beep at me.

Green to green is low, 1-5 MOhms and has continuity

Green to the blue connector on the alternator is also 120 and no continuity

 

[Mattax]

The carbon brushes are fairly high resistance when the rotor isn't spinning. Its possible the rotor is OK.

High resistance or open connection in the J2G segment (blue) would alone explain the alternator not working.

 

[SputnikOne]

You think the issue is in the blue wire itself somewhere?

 

[SputnikOne]

Blue pin looks fine to me, besides the obvious extra wire

 

[Mattax]

On the battery terminals I use somehting pretty abrassive - wire brush or more often emery.
Everything else I prefer to be more gentle with.
I'll use De-oxit and electrical contact cleaner and somehting to scrub it, whether cloth, or a nylon brush (toothbrush), or sometimes if its not plated, fine steel wool. But my favorite scrubber is a fiberglass contact cleaner

Lots of ideas here

Cleaning bulkhead connectors

Want to clean the bulkhead connectors while motor is out I have elec spray cleaner but was wondering what ya'll use to get into the connectors and give them a good scrubbin

www.forabodiesonly.com

 

[Mattax]

Blue pin looks fine to me, besides the obvious extra wire

View attachment 1716410351

I don't know.
Look at the crimps.
Then find a good spot to get the multimeter probe or aligator clip touching good copper. Do the same for the field terminal that attaches to the alternator.
If there is still an open connection, then there is a break somewher between the two probe points.

I'll say from the photo that looks like double wire terminal. Otther side should look like this.

If the the wire strands are all solid, then just clean it. If there is a break its furthe downstream.

 

[SputnikOne]

Pulled the blue terminal off of the alternator to get a better reading on it, got varying levels depending on where I put the probe, cleaned it off with a wire brush.

 

[SputnikOne]

Removed the connector for the alternator from the pin and cleaned the area where they join, reattached it and getting .3 ohms or less from engine connector pin to alternator pin now.

 

[Mattax]

Pulled the blue terminal off of the alternator to get a better reading on it, got varying levels depending on where I put the probe, cleaned it off with a wire brush.

View attachment 1716410360

View attachment 1716410361

Well those don't look like factory connectors.

.24 Ohms is getting to the lower limit of what a standard meter can read.
If the terminal on there is OK (I have a predjudice against those cheap squeez connectors) then there should have been power flowing through.
That will have to be tested live as @67Dart273 described.

Since you have the brushes off, you can measure the rotor's resistance from slip ring to slip ring. Off the top of my head it should be about 3 ohms.
I say that not knowing if you can really get a probe into both brush locations with the alternator on the engine. With a slant six it may be possible.
When you reassemble, it is critical that both brushes go into their insulators, and that the screws have thier insulating fiber washers.

 

[SputnikOne]

On that note, I'm not super sure how all these pieces on the alternator go back together, when I loosened the bolt it all kinda just came out and I didn't get a good look at how it was assembled.

I think there was a miniscule amount of power flowing through, as I said earlier the ammeter moved the *tiniest* but if I gave it alot of throttle, may have just been the resistance.

I assume the black washer is the fiber one, what about the one already on the bolt?

 

[SputnikOne]

Ah, I didn't see your picture before, I'll see if it all goes back together.

 

[Mattax]

Added the photo.
Normally we just remove the push termimals

If you have them both out, measure resistance slip ring to slip ring

Identifying Chrysler Alternators (1960-1976)

Roundback and Squareback refer to the style of housing. Roundback through model year 1969. Roundback for model years 1970-71 usually has a slightly different rear housing Squareback Revised Squareback Is most easily differentiated by the thin middle between the housings. Overall these...

www.forabodiesonly.com

 

[SputnikOne]

Bouncing between 3 and 4 ohms.

 

[SputnikOne]

The green wires terminal has seen better days, and the wire itself just popped out rather easy and I was wiggling the connector loose

 

[Mattax]

Bouncing between 3 and 4 ohms.

That's good.

The green wires terminal has seen better days, and the wire itself just popped out rather easy and I was wiggling the connector loose

View attachment 1716410369

Did I mention that I have predjudice against that type of cheap terminal?
That pretty much tells us the quality of the connection was garbage.

If you must use that type of terminal see what the Marine Supply has. Blue Sea and Ancor have some 1/4" push-ons that are a little better than the auto parts stores have.
here's one

Its important not to cut the wire so short as to put it under stress when connected. Originally there was a little support bracket on the alternator to help keep the wire from being vibrated or similarly stressed.

 

[SputnikOne]

Ah..