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Topic: 86 bird w/289 wont hold charge???? (Read 2473 times) previous topic - next topic

86 bird w/289 wont hold charge????

my bird wont hold a charge, I've put a new alternator in it, with the battery charged up it'll run for a few minutes then die, and wont restart. I think the amp gage is stuck as well, does anyone have any idea what might be the problem???
86 Thunderbird TurboCoupe, 66 289 HI-PO, auto.
--------------------------------------------------------------
Hoof beats may be faster than heartbeats, but birds are faster than ponies!

86 bird w/289 wont hold charge????

Reply #1 –
Sounds like your altenator isnt working, but if its new, you may have a short somewhere drawing power. Or the altenator charge is making to battery.  If battery had a dead/weak cell car should run fine, with new altenator. Just have problems if it sits for a while.

There is a fuseible link for the Alt that hooks to the starter relay, if the 86 birds are like the 87-88's and like the mustangs.  Not sure on color but should be tell you in Haynes/Chilton manual.. If that fusible link is blown, then alt isnt charging battery and that is your problem.

86 bird w/289 wont hold charge????

Reply #2 –
ok, that makes sense, does anyone know where that is so I can find it?
86 Thunderbird TurboCoupe, 66 289 HI-PO, auto.
--------------------------------------------------------------
Hoof beats may be faster than heartbeats, but birds are faster than ponies!

86 bird w/289 wont hold charge????

Reply #3 –
With your engine running you should have about 14 volts at the battery.  If you do than the alternator is working and it's most likely the battery.  A common problem is replacement battery cable ends get dirty where they clamp on to the cable (if you have these).

TED

86 bird w/289 wont hold charge????

Reply #4 –
search under electrical tech using "3g" as the search.

there are a ton of wiring diagrams on this.

your v8 swap might have a conflict with the factory harness somewhere.

usually i post lots of electricl diagrams of the 87/88 cars while most wiring is the same on 83-88, in this case i would tread softly on the charge circuit.  there are many changes and things id rather not get into on this to keep the thread on topic.  I will assume your running a carb, correct?  if so, the problem will be all the more easy to find.



"softtouch" ususally posts lots of wiring diagrams of pre87 which might be more applicable to you.  this 2.3 harness can be a devil but only so if you dont have diagrams and you shot gun it.
There is a shunt that captures your milivolt drop across a section of wire that drives the amp meter, just fyi if that is blown then you may have just found your problem.

search all threads in electrical tech by jcassity and softtouch,, thats where I think you should start for diagrams.

your description is vague but "stuck" means it is now moving,,or sitting in one spot mid way or sitting at max?

also, sometimes people end up destroying a new alternator just becaue the existing battery is bad.  replacing both as a matched set is the best way.  You must have had a reason for replacing the alt,, such as the old one was not putting out power ect.  What caused the old alt to go bad? was if very old or what.

86 bird w/289 wont hold charge????

Reply #5 –
ok, another question, I've had a few people tell me to "just go get a 2 wire chevy alt. and put on it, that should fix it"  has anyone done this. normaly I say its a sacrelige, to put a chevy part on a ford, but if it works then I'm willing to try it.  Any takers?
86 Thunderbird TurboCoupe, 66 289 HI-PO, auto.
--------------------------------------------------------------
Hoof beats may be faster than heartbeats, but birds are faster than ponies!

86 bird w/289 wont hold charge????

Reply #6 –
Quote from: shameless;331672
ok, another question, I've had a few people tell me to "just go get a 2 wire chevy alt. and put on it, that should fix it"  has anyone done this. normaly I say its a sacrelige, to put a chevy part on a ford, but if it works then I'm willing to try it.  Any takers?



yes,, ill take it youve been given bad advice.

lets find your problem.
can you use a meter?

im guessing off the bat you have a fuse link from the alt yielding an open circuit.

follow the brown/yellow strip wires up to the alternator,,and while im at it, did you also replace the engine harness connector ?  I know for a good while there, the alternators were sold with a replacement connector.

86 bird w/289 wont hold charge????

Reply #7 –
Does this car have an external voltage regulator?  Meter the battery voltage with the car running like Ted mentioned and post back.  From there I bet money the problem can be tracked down.  There just is not that much to the charging system on these cars that will cause a problem like this...battery, alternator, regulator, cables, and fusible links.  It could be a broken wire but once all the rest check out we can get to that as well.

Darren

83 351W TKO'd T-Bird on the bottle


93 331 Mustang Coupe - 368 rwhp

86 bird w/289 wont hold charge????

Reply #8 –
Quote from: shameless;331672
ok, another question, I've had a few people tell me to "just go get a 2 wire chevy alt. and put on it, that should fix it"  has anyone done this. normaly I say its a sacrelige, to put a chevy part on a ford, but if it works then I'm willing to try it.  Any takers?


Apparently the smallminded people that tell you that have no knowledge of a 3G alternator. No difference in wiring difficulty, and it's Ford.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)

86 bird w/289 wont hold charge????

Reply #9 –
Quote from: shameless;328828
my bird wont hold a charge, I've put a new alternator in it, with the battery charged up it'll run for a few minutes then die, and wont restart.

With a good fully charged battery, the car should run for hours not a few minutes with an alternator that is not working.
If a good fully charged battery is discharging that fast, something should be hot enough to be smoking.

Is the charging problem something that used to work or something you never got working since swapping the engine?

Do you have a meter to trouble shoot with?

The alternator field current should be turned on with the key in run.
Don't start the car.
With a hacksaw blade or a non-magnetized screwdriver feel for magnetism on the laminated plates part of the alternator.
Key off no magnetism. Key on magnetism.

According to the 86 EVTM your car came with a 1G alternator and an external voltage regulator. Is this what you are still using?

Look at this link to ID what alternator you have.
http://fordfuelinjection.com/index.php?p=63

86 bird w/289 wont hold charge????

Reply #10 –
I'm not sure what kind of alternator it is, it has 3 or 4 post I think, but I run the same alternator in my 79 ford and it only uses 3 or the post, and it works great in it.  Yes, it has an ext. regulator.  I'm not quite sure how to use a multi meter, but I'll have a friend come over and help me with it, thanks for the advice so far, I'm pretty knowlegeless when it comes to this stuff.
86 Thunderbird TurboCoupe, 66 289 HI-PO, auto.
--------------------------------------------------------------
Hoof beats may be faster than heartbeats, but birds are faster than ponies!

86 bird w/289 wont hold charge????

Reply #11 –
Since your car has an ammeter instead of a battery light, your alternator should have 2 wires.

1. Check your battery voltage. Should be 12.4 volts.

2. Check that you have battery voltage on the "B" terminal of the alternator. That's the big BK/O wire with the nut on it.

3. Check that you have battery voltage on the Y/W wire to the "A" terminal of the voltage regulator.

4. Check that the O/LB wire from the regulator "F" terminal is on the alternator "F" terminal.

5. With the key on, check that you have battery voltage on the LG/R wire to the "S" terminal of the voltage regulator.

6. With the key on, check for magnetism on the laminated plates part of the alternator.

7. With the engine running the battery voltage should be 14.5 volts.

86 bird w/289 wont hold charge????

Reply #12 –
mine has 3 wires on it, looks factory, but could be someones hack job.
86 Thunderbird TurboCoupe, 66 289 HI-PO, auto.
--------------------------------------------------------------
Hoof beats may be faster than heartbeats, but birds are faster than ponies!

86 bird w/289 wont hold charge????

Reply #13 –
Can you post the color codes of the wires on the alt?
How many wires on the regulator and what are the color codes?
Did your buddy show up with his meter?
Did you do the magnetism check?
Is it a factory ammeter or aftermarket?

86 bird w/289 wont hold charge????

Reply #14 –
Quote from: shameless;332657
mine has 3 wires on it, looks factory, but could be someones hack job.

All I have to go by are the EVTM's. Vehicles that have a battery/alternator light on the dash have three wires on the alternator.
85 and 86 Turbo Coupes are shown with the ammeter and have two wires on the alternator.
I understand how this stuff works and can give you all that kind of info you want, but I don't want to be the guy that tells you how to build a watch when you ask for the time.

I can't guess how your car wound up like it is, but with some feedback from you I can help you figure out if the alternator is working and if not why not.

The basic tool you need is a multi-meter. Multi means it can be three different meters, ohm meter, ammeter and volt meter. You will use the volt meter function for checking the alternator.
You only need an inexpensive one. You can pick one up at a hardware store.