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Correct, The red wire goes to the battery, but it is not the one getting hot (though it is sometimes hot, but not melting). The black wire is the alternator wire and it is the one getting hot. I will check where the - battery cable goes.
I cleaned the braided wire with electrical cleaner before along with the alternator wires and connectors (without disconnecting).
Ok the braided wire I would remove and use wire brush or even better sand paper on the wire and where it bolts to so it is nice and shinny.
Also if you don't have one add a ground cable from motor to the frame.
As for the hot wires that is a sign of a bad/dirty connection. Disconnect the batt. remove all the wires from the solenoid where they get hot. Take sand paper and make all connections shinny then put them back.
From the pictures it looks like the nut on the solenoid holding the "hot" wires is not tight. I say this because it looks like the lock washer is not flat and some gaps between the wire connections.
Thing is to get it tight but not break it.
Dave ----
I will try to get another ground in the future. The current bracket connects to the engine and the braided wire hooks to it and to the frame. Where else would I need one? I will tighten the nut. As you have warned against I have broken off a stud before and now am weary of tightening. I will also clean them. Will the bad/loose connection also cause the alternator to get that hot?
Okay, so the infamous 2G "firestarter" alternator is acting up on yet another truck....
My first suggestion would be to replace the charge plug/pigtail per Ford's technical service bulletin 96214.
These pigtails are available in the aftermarket from at least seven different manufacturers.
(I would find my old posts listing part#'s but it's a pita on my phone)
Thank you, Jim, my first comment was going to be that this is a 2G alternator.
hharris I agree with all the sugegstions given, might unplug the harness from the connection on the alternator and clean & inspect; that connection has been known to overheat and cause fires.
Several years ago, we had a guy here named grubbworm who posted some charging system diagnostics that people here liked so I copied his stuff to the FAQs subforum, they're here, hope you can read them:
Jim @ArdWrknTrk could you please look over that stuff and see if you agree with it? You know lots more about this stuff than I do, I'm just trying to help the guy.
~~
hharris: My sister races her 1990 Mustang at Bandimere Speedway (I go just as moral support), she won a 3rd-place trophy today.
Chris,
I was *also* thinking that "....'70's 302......must have a first gen alternator", but not so!
The 2G alternator has an internal regulator, so I would have to say that the bottom of the 3-point test (below the bold black line) and Dave Franklin's diagram do not apply.
It is impossible to see the plug or pigtail of hharris8's truck because of the black sleeve that is ziptie'd on.
Usually what happens is that the contacts in the plug corrode and then it gets hot enough to either melt the wires together or the contact shorts to the alternator case..
Either way, that harness will burn (and there will be little warning because you can't see through the braided cover)
This is the *rectangular* charge plug, with two 10Ga black/orange wires spliced to a single fusible link and the white/black stator wire.
The regulator plug will be oval or 'D' shaped and have yellow/white 'sense' and the lt grn/red 'excite' wire.
This plug is usually just fine unless the charge harness melts into it.
Chris,
I was *also* thinking that "....'70's 302......must have a first gen alternator", but not so!
The 2G alternator has an internal regulator, so I would have to say that the bottom of the 3-point test (below the bold black line) and Dave Franklin's diagram do not apply.
It is impossible to see the plug or pigtail of hharris8's truck because of the black sleeve that is ziptie'd on.
Usually what happens is that the contacts in the plug corrode and then it gets hot enough to either melt the wires together or the contact shorts to the alternator case..
Either way, that harness will burn (and there will be little warning because you can't see through the braided cover)
This is the *rectangular* charge plug, with two 10Ga black/orange wires spliced to a single fusible link and the white/black stator wire.
The regulator plug will be oval or 'D' shaped and have yellow/white 'sense', lt grn/red 'excite', and the other end of the white/black 'stator' wire.
This plug is usually just fine unless the charge harness melts into it.
So what would you suggest I look at ArdWrknTrk? Should I remove the black sleeve?
I sanded all contacts and terminals on the solenoid, battery, and alternator bracket (neg battery cable and braided wire). I could not disconnect the braided wire from the frame because the bolt (which was tight) kept spinning without coming up.) I tested and as soon as the battery is connected the black wire heats up.
I have read these G2 alternators have given a lot of people trouble (which ArdWrkTrk already mentioned). Should I convert to 3g and how much more would that cost than replacing the 2G?
I will try to get another ground in the future. The current bracket connects to the engine and the braided wire hooks to it and to the frame. Where else would I need one? I will tighten the nut. As you have warned against I have broken off a stud before and now am weary of tightening. I will also clean them. Will the bad/loose connection also cause the alternator to get that hot?
Sorry I left you hanging had to get to bed as I had to be up at 12:30 for work. It is lovely getting only 4 hours sleep before work!
The braided cable I thought went from the ALT bracket to the body, inner fender well? If it does go to the frame then you are ok other than that bolt you cant remove because it turns.
Is this a nut & bolt or self taping bolt and can you get to the other side of it?
I would do what ever it takes to remove / replace that bolt so it will it will get tight after a good cleaning.
Do you have a heavy ground wire / cable from frame to body? Some NEG batt cables have a wire on them that you can add to and bolt it to the body like the fender or radiator support.
Now on to that 2G & 3G ALT's that is out of my league so you will have to listen to others on that. I think till you find the reason and fix it I would remove that covering so you can keep an eye on the wires.
Besides it sounds like you may just need to replace the plug on the ALT and be ok so would need to get to the wires any way.
Should I convert to 3g and how much more would that cost than replacing the 2G?
Nobody is talking about replacing the 2G alternator, what we're talking about is the connector on the wiring harness that plugs into the alternator; that thing melts and starts fires, it's a well-known Ford problem. I would remove the alternator and take a look at everything, as Jim said that connector is available from many places.
As for converting to a 3G setup, this is from the HOWTOs subforum:
Sorry I left you hanging had to get to bed as I had to be up at 12:30 for work. It is lovely getting only 4 hours sleep before work!
The braided cable I thought went from the ALT bracket to the body, inner fender well? If it does go to the frame then you are ok other than that bolt you cant remove because it turns.
Is this a nut & bolt or self taping bolt and can you get to the other side of it?
I would do what ever it takes to remove / replace that bolt so it will it will get tight after a good cleaning.
Do you have a heavy ground wire / cable from frame to body? Some NEG batt cables have a wire on them that you can add to and bolt it to the body like the fender or radiator support.
Now on to that 2G & 3G ALT's that is out of my league so you will have to listen to others on that. I think till you find the reason and fix it I would remove that covering so you can keep an eye on the wires.
Besides it sounds like you may just need to replace the plug on the ALT and be ok so would need to get to the wires any way.
Good luck
Dave ----
No problem. What job requires such demanding hours? I was working on classes all day anyway. I will try and get at that screw from the bottom tomorrow. Any tips on how to pull it?
This is the two wire connector. It is covered in some sticky gold substance that does not look or feel like oil. Maybe it has something to do with the electrical cleaner.
The three wire connector has some melting bu I do not know if it is because of the wires or because the alternator got so hot.
Not sure what is inside the connector. Melted wires?
whatever is inside the three prong connector can be scraped out like soft sticky wax. The gray plastic on the back of the two prong connector is falling apart, but that is just insulation so it should not cause trouble I would not think.
