alternator - charging help (posted pics and specs)

In the first picture, the heavy red wire goes to the battery to charge it not to the plug on the alternator. Then you have a smaller gauge white wire go to a fuse. Take the heaviest wire you can get [10 ga minimum] and run it from the Bat terminal on the back of the altrernator and connect it to the + terminal of the battery then you run a wire from the Bat terminal on the alternator to the #2 terminal on the side of the alternaror, this can be a smaller gauge wire.

 

I think the red wire from the connector is the voltage sense wire, so it's essentially taking a 3-wire alternator and turning it into a 1-wire alternator. The voltage regulator is trying to hold the voltage steady right at the BAT terminal.

 

That's correct... the sense wire is just connected to the heavy gauge wire that does go to the + batt terminal.. if you look closely you can see it in the pic.

 

The redish wire going from the alternator to the battery looks a little dicey, I'd replace that one. The indicator wire looks fine, which could explain whey the alternator is showing a good charge but not actually doing it.

 

Just a quick note, as I tested the voltage when it was running:

Voltage between battery + & - while running = 14.3x

Voltage between "batt" terminal on alternator and ground on frame = 14.3x

 

One more guess...

Should the batter be directly connected to the alternator or should they share a post at the solenoid? See this diagram...

http://www.earlycj5.com/forums/showthread.php?t=61306

 

In this picture:



What does the splice look like that is underneath the white tape? I might be inclined to replace this wire and confirm that it's not the culprit.

 

There are 2 connectors on the side. I believe the #1 is the warning light the #2 is the voltage sensing terminal. This might help.

http://www.oldengine.org/unfaq/10si.htm

 

We did test that wire... as indicated by rallyroach above...

After doing some more research I don't believe it is wiring or alternator related at this point... I think it is a bad ignition control module... it has the exact symptoms when it fails...info from this site: (temperature failure section)
http://www.ehow.com/list_6300728_faulty-ignition-control-module-symptoms.html

that would explain why the battery is still reading fully charged after it dies... thoughts on this theory?

 

OK so the wire coming off the bat goes to the positive terminal of the battery, I bet that splice is the culprit, I wiuld replace it with a new wire with good terminals. Also the wite wire needs to go on the top terminal on the side of the alternator.Since it is indirectally connected to the battery it will be hot all the time so there is a constant feed thru the fuse pannel.

 

My thoughts exactly! Did some thinking about this today and that's what sounded reasonable to me. Module heats up and quits..let it cool down and it runs. Your battery is reading good when the engine dies so I would think you've come up with the best idea yet.

 

That brings me to a new question... someone years ago upgraded the ignition to a mallory module/coil and distributor cap. Looks like a complete kit.

Do you think I will be able to put a stock CJ coil/module back in?? I can no longer locate the mallory part... Probably from the 80's.

 

I would think that would work, if nothing has been changed in the distributor.
You might want to consider putting in a Ford TFI ignition in place of the stock system. There are write-ups on how to make that change. I did it to my 73 and love it. Mine uses the GM 4 pin module and an 86 AMC electronic distributor. Not an expensive mod, but really worthwhile.

 

The mallory system is a complete replacement. Mallory hall effect trigger inside the dizzy, with a new rotor to match, and a mallory Cap, leading to the mallory coil :/

It would need a whole new system from the distributor out.

Also: I'd love to rip the guts off this thing and put on a proper MSD 6-AL box like I run in my Toyota. That never fails me as long as the coil doesn't get shaken to death on the rocks...

 

Well in that case I guess you're stuck with changing out the whole thing. I'm not familiar with the Mallory system, so I'll leave any advice about it to others.

 

You stated that the spark is weak right after it dies. That tells me the module is still triggering (as it is supposed to) but the coil windings are shorting out to each other which will reduce the output spark. If you have a standard coil that uses an external resistor, I would try that and see what happens. It may not run great as you have the plugs gapped wider for the high output coil but if it runs for 30-40 minutes, that will tell you something.

 

Yes... I think at this point I will try the following:

1. test or change the coil
2. test the module
3. Swap out for the TFI upgrade since I am replacing parts anyway... will probably need a new total distributor though... as ours doesn't look stock :\

 

You could go H.E.I.

 

The TFI just looks easier and cheaper...

 

I had an idea... but proved myself wrong.. so I edited this post