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Alternator not charging

  • Thread starter Thread starter DissFigured
  • Start date Start date Nov 1, 2005

DissFigured

New Member
Apr 26, 2005
320
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0
Dallas, TX
Nov 1, 2005
#1
  • Nov 1, 2005
  • #1
I just replaced the alternator and the distributor.

Before doing so, the alt light was on and it was running crappy. So, I replaced those two components, and now it runs like a dream until......


I tried to start it after turning it off, and it barely turns over.
My assumption is that once started, the car runs off the alternator and so the alternator is providing enough power to run the car and lights, radio etc... Is that correct?

However, it doesn't seem to be charging the battery. No ALT warning light comes on when driving but it is able to turn over less and less w/ every start until now where it won't start at all.

I am currently verifying everything w/ wiring diagrams in my manual, and scouring forums but I didn;t know if anyone had any quick thoughts that might help.
 

latamud

Founding Member
Oct 22, 2002
791
2
19
Tampa, FL
Nov 1, 2005
#2
  • Nov 1, 2005
  • #2
You're possibly running just off the battery. Maybe something loose at the regulator?
 
T

ttoney

Member
Sep 12, 2005
195
0
16
Denver
Nov 1, 2005
#3
  • Nov 1, 2005
  • #3
Yeah, sounds like it is running off the Batt. Junp it then pull the positive cable from the Batt. If it dies the charging circuit has an issue, or the Alt itself is not working properly.
 
G

gevalia

New Member
May 18, 2004
20
0
0
Nov 2, 2005
#4
  • Nov 2, 2005
  • #4
Check your ground

Had same problem with chassis ground wire. Would turn over 7 or 8 times before I'd have to recharge.
 

68 Coop

New Member
Aug 13, 2005
104
0
0
Mesquite, NV
Nov 2, 2005
#5
  • Nov 2, 2005
  • #5
How old is the battery, and how long have you thought the alternator was bad??? If it's been running on just battery for a long time, I'd just get a new one. Might save ya down the road, and winter is just around the corner.
 

DissFigured

New Member
Apr 26, 2005
320
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0
Dallas, TX
Nov 2, 2005
#6
  • Nov 2, 2005
  • #6
Battery is 6 months old. I thought the alternator was bad for about a week due to the warning light. Turned out not to be the alternator at all but the condenser in the distributor. I replaced the alternator anyway along w/ the distributor
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Nov 2, 2005
#7
  • Nov 2, 2005
  • #7
You're copletely forgetting the voltage regulator, the old solid state ones were famous for burning out. I can't figure out why you think the condensor in the distributor would have something to do with the charging system.
 

Pbum5

Member
Oct 27, 2004
515
0
17
Minneapolis, MN
Nov 2, 2005
#8
  • Nov 2, 2005
  • #8
Yup,
D.Hearne has a point.
It could very well be the Voltage regulator.

If not, and all of your wires are properly hooked up it could also be the alternator.

It is not uncommon for remanufactured alternators to be faulty.
 

DissFigured

New Member
Apr 26, 2005
320
0
0
Dallas, TX
Nov 2, 2005
#9
  • Nov 2, 2005
  • #9
It is like this:
First, I got the wrong book aparently. I am still waiting on the ford shop manual so I resorted to the forums.

1st symptom: Car starts running real crappy like timing is out. Folks pointed me in the direction of the distributor citing the points or condensor.

2nd Symptom: Around that same time, the ALT light began coming on at times. So I figure what the heck, mine is old, I will replace that too.

Up until then, I had never had a problem with the battery not charging. So My assumption at this point is either I hooked up the alternator incorrectly or in doing so, I somehow created a short.


Additionally, it should be noted that I know very little about this stuff and I am learning as I go.
 

DissFigured

New Member
Apr 26, 2005
320
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0
Dallas, TX
Nov 2, 2005
#10
  • Nov 2, 2005
  • #10
Additionally, I have another question. When I put the alternator in, I notice the fan on the alt is hitting the bottom bracket. Anyone had this problem before? I can;t figure out how it was ever able to clear the fan before.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Nov 2, 2005
#11
  • Nov 2, 2005
  • #11
It's been my experience that when the condensor in the distributor goes bad, it won't fire at all. Best thing there is to replace both points and condensor with a Pertronix unit. Remove the alternator again, go have it checked, then put it back with a new voltage regulator and before starting the car, make sure the battery is fully charged.
 

FORCED2DV8

New Member
Jun 6, 2005
458
0
0
Grand Rapids MI
Nov 2, 2005
#12
  • Nov 2, 2005
  • #12
Take a meter with the car running, put it on the battery terminals, you should get a reading of 13 to 14.5 volts if the alt is operating correctly, this includes voltage regulator, if not then test at the regulator, second with car off measure voltage at battery, it should be 12 volts +, this does not mean its always good, since you cannot measure amps, but if alt and regulator test good, and of course your connections are good, grounds and such then its your battery.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Nov 2, 2005
#13
  • Nov 2, 2005
  • #13
It's been my experience that when the condensor in the distributor goes bad, it won't fire at all. Best thing there is to replace both points and condensor with a Pertronix unit. Remove the alternator again, go have it checked, then put it back with a new voltage regulator and before starting the car, make sure the battery is fully charged.
 

krash kendall

Active Member
Nov 19, 2004
1,258
0
36
Aldergrove, B.C. Canada
Nov 2, 2005
#14
  • Nov 2, 2005
  • #14
D.Hearne said:
It's been my experience that when the condensor in the distributor goes bad, it won't fire at all. Best thing there is to replace both points and condensor with a Pertronix unit. Remove the alternator again, go have it checked, then put it back with a new voltage regulator and before starting the car, make sure the battery is fully charged.
Click to expand...

Here's the history lesson Dave, be sure to read all Pakrat's sage advice regarding the Ford Manual, which Dissfigured appears to have ordered. http://forums.stangnet.com/showthread.php?t=590522

Hey Dissfigured, I have to say you really should get a multimeter if you want to diagnose any electrical problem. They are cheap and way better than a test light.
 

DissFigured

New Member
Apr 26, 2005
320
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0
Dallas, TX
Nov 2, 2005
#15
  • Nov 2, 2005
  • #15
Before I go trash talking auto stores, is there a logical reason that the alternator that I bought from Pep Boys was bad?

I assume that when they remanufacture one, they test it. That turned out to be the issue anyway. I took it in, he put it on the machine and shook his head.

None the less, I got another one and the guy didn't want to test the new one. He just looked it over and said "This one is good" Now they are identical and I bought them 2 days apart so I am not sure what he saw.

I made him test it there before I would take it and it passed 14.5 volts. I put it in the car, and everything is once again functioning properly.

So, can they go bad sitting on the shelf? I didn;t see a sell by date so I imagine not.
 

jes72mustang

New Member
Mar 31, 2005
224
1
0
S. Central PA
Nov 3, 2005
#16
  • Nov 3, 2005
  • #16
I had a similar problem in my 72, battery didn't seem to be recharging. And one day while out driving the car just died, and would not turn back over. The battery was stone dead. I had just made it to my in-laws house. Threw the battery on his charger for a few hours and put it back in car started fine. Further investigation I found one of the wires from the alt to the voltage regulator severly frayed like only one strand of copper maintaining the connection. Ordered a new altenator wiring harness and have had no problems since.
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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0
south louisiana
Nov 3, 2005
#17
  • Nov 3, 2005
  • #17
DissFigured said:
Before I go trash talking auto stores, is there a logical reason that the alternator that I bought from Pep Boys was bad?

I assume that when they remanufacture one, they test it. That turned out to be the issue anyway. I took it in, he put it on the machine and shook his head.

None the less, I got another one and the guy didn't want to test the new one. He just looked it over and said "This one is good" Now they are identical and I bought them 2 days apart so I am not sure what he saw.

I made him test it there before I would take it and it passed 14.5 volts. I put it in the car, and everything is once again functioning properly.

So, can they go bad sitting on the shelf? I didn;t see a sell by date so I imagine not.
Click to expand...
They don't go bad on the shelf, that just happens to food If you get a bad one from the shelf, it was just cleaned and painted, nothing more, nothing less. I've seen it happen dozens of times. "Quality Control" ? Yea, right.
 

krash kendall

Active Member
Nov 19, 2004
1,258
0
36
Aldergrove, B.C. Canada
Nov 3, 2005
#18
  • Nov 3, 2005
  • #18
You will quite often find the same problem with reconditioned master cylinders.
 

krash kendall

Active Member
Nov 19, 2004
1,258
0
36
Aldergrove, B.C. Canada
Dec 20, 2005
#19
  • Dec 20, 2005
  • #19
Hey Dissfigured, I just PM'd you back.....finally.
 
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