Notices
1948 - 1956 F1, F100 & Larger F-Series Trucks Discuss the Fat Fendered and Classic Ford Trucks

wiring for charging system

Thread Tools
 
Search this Thread
 
Old Feb 19, 2006 | 02:38 PM
  #1  
pootscratch89's Avatar
pootscratch89
Thread Starter
|
Senior User
Joined: Apr 2005
Posts: 207
Likes: 0
From: Burkburnett, Texas
wiring for charging system

Need some help please. I installed another ground wire from my engine to the frame--all ground wires are good; still not charging above 12V. I'm not sure that the wiring from the voltage regulator to the altenator is 100% correct. Can anyone tell me how the voltage regulator and altenator is supposed to be wired? It is a standard ford small block (351W) altenator and charging system. Please help--I have to get this truck going today!
 
Reply
Old Feb 19, 2006 | 05:37 PM
  #2  
Christopher2's Avatar
Christopher2
Fleet Mechanic
Veteran: Navy
20 Year Member
Photoriffic
Community Favorite
Joined: Jun 2004
Posts: 1,791
Likes: 47
From: Minnesota
Club FTE Gold Member
Post

I have a 1976 to 1986 repair manual and you really need to know what you have they are not all the same wiring. Here are the parts that seem to be common between 1976 - 1983. This entire wiring diagram changes in 1984
  1. Alternator B terminal - black / red wire goes to the starter solenoid side that is conencted to the battery. The yellow A+ on alternator regulator is tied to this wire. My guess would be this is the voltage sensing wire the controlles the ouput of the alternator.
  2. Alternator S terminal - white / black wire goes to the S on the alternator regulator. My guess is that this is the stator wire.
  3. Alternator F terminal - Orange wire goes to the F on the alternator regulator. My guess would be that it is the field wire.
  4. Alternator Regulator - I terminal this one is a little harder it shows that the red / green wire goes to alternator indicator, the brown wire in the starter relay and the ignition switch. My guess would be this wire turns on and off with the ignition.
 
Reply
Old Feb 19, 2006 | 06:33 PM
  #3  
TBucketJack's Avatar
TBucketJack
Senior User
Joined: Jul 2004
Posts: 203
Likes: 0
From: Glendale, AZ
Try running a ground from the case of the alternator to the frame.
 
Reply
Old Feb 20, 2006 | 10:39 AM
  #4  
pootscratch89's Avatar
pootscratch89
Thread Starter
|
Senior User
Joined: Apr 2005
Posts: 207
Likes: 0
From: Burkburnett, Texas
Thanks Chris and Jack... Someone in another post told me to make sure the idiot light is connected--I know I diked it off. I am hoping that is the problem. I changed my ground wires around, and even ran some extra ones--still no change. Thanks for the wiring help. I'm going to trace the wires out this morning.
 
Reply
Old Feb 20, 2006 | 12:30 PM
  #5  
AXracer's Avatar
AXracer
Hotshot
20 Year Member
Liked
Joined: Oct 2004
Posts: 15,882
Likes: 88
From: Durham NC
Unless your battery is run down, what's wrong with 12V output into a charged battery?
 
Reply
Old Feb 20, 2006 | 02:21 PM
  #6  
55forder's Avatar
55forder
Elder User
20 Year Member
Joined: Apr 2001
Posts: 673
Likes: 1
From: San Diego
Check out this link.

http://www.americanstreetmasters.com/Wiring_101_4.jpg

Rich
 
Reply
Old Feb 20, 2006 | 03:14 PM
  #7  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
Originally Posted by pootscratch89
Thanks Chris and Jack... Someone in another post told me to make sure the idiot light is connected--I know I diked it off. I am hoping that is the problem. I changed my ground wires around, and even ran some extra ones--still no change. Thanks for the wiring help. I'm going to trace the wires out this morning.
The Light will not stop it from charging.
This Diagram should be the same as your 1957.

 
Reply
Old Feb 20, 2006 | 06:00 PM
  #8  
Christopher2's Avatar
Christopher2
Fleet Mechanic
Veteran: Navy
20 Year Member
Photoriffic
Community Favorite
Joined: Jun 2004
Posts: 1,791
Likes: 47
From: Minnesota
Club FTE Gold Member
This diagram is for a generator not an alternator.



Originally Posted by subford
The Light will not stop it from charging.
This Diagram should be the same as your 1957.

 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

10 Ways Ford is LOSING to the Competition

 Joe Kucinski
story-1

Top 6 Best Deals Available on New Fords & Lincolns Right Now

 Brett Foote
story-2

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-3

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-4

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-5

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-6

Every 2026 Ford Engine Explained

 Brett Foote
story-7

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-8

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-9

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
Old Feb 20, 2006 | 06:13 PM
  #9  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
Originally Posted by Christopher2
This diagram is for a generator not an alternator.
Sorry I missed when he said alternator, I just noticed it was for a 1957 Ford.
Here is one for an alternator from the 70's.
The light has to be there on this one.

 

Last edited by subford; Feb 20, 2006 at 06:16 PM.
Reply
Old Feb 20, 2006 | 07:42 PM
  #10  
pootscratch89's Avatar
pootscratch89
Thread Starter
|
Senior User
Joined: Apr 2005
Posts: 207
Likes: 0
From: Burkburnett, Texas
Thanks for the diagrams... I hooked the indicator light up, and it still drops below 12V when you turn everything on. Plus, I disconnected the negative wire from the battery while the truck was running; the engine died. I should be able to completely disconnect the battery while it is running--correct? I just don't know what else to try short of completely rewiring everything...
 

Last edited by pootscratch89; Feb 20, 2006 at 07:48 PM.
Reply
Old Feb 20, 2006 | 07:52 PM
  #11  
jaye's Avatar
jaye
Posting Guru
25 Year Member
Joined: Aug 2000
Posts: 1,849
Likes: 0
From: S.C.
Try painless wiring's web site they have various wiring diagrams on their site. Go to google and do a painless wire search.
Jaye
 
Reply
Old Feb 20, 2006 | 08:29 PM
  #12  
mason55's Avatar
mason55
Tuned
Joined: Jun 2005
Posts: 299
Likes: 2
From: Marryville, Tennessee
Sounds like a bad alternator. Should run just the same after started off the Alternator w/o battery. Have the alternator tested and go from there.
 
Reply
Old Feb 20, 2006 | 08:30 PM
  #13  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
Originally Posted by pootscratch89
Thanks for the diagrams... I hooked the indicator light up, and it still drops below 12V when you turn everything on. Plus, I disconnected the negative wire from the battery while the truck was running; the engine died. I should be able to completely disconnect the battery while it is running--correct? I just don't know what else to try short of completely rewiring everything...
It should have about 13.5 Volts at the battery while running, 12 Volts is a discharged battery.

A 12 Volts reading at the battery with the engine running means the Alternator is not charging.

However it is normal for the engine to die after about two to three minutes when the battery has been disconnected with a good alternator. The alternator does not have the capability of holding magnetism in it field. An alternator must have a small DC feed to its field to produce power.

 
Reply
Old Feb 23, 2006 | 09:04 AM
  #14  
black58's Avatar
black58
Elder User
Joined: Nov 2003
Posts: 576
Likes: 9
From: Rockford, IL
Originally Posted by subford
The Light will not stop it from charging.
The light will stop it from charging. On my truck I had the same problem. I hooked up an ammeter and couldn't figure it out. As soon as I spliced the idiot light back on the ammeter jumped to charge. I think I just took the bulb out then. I know it sounds wierd but it worked. John
 

Last edited by black58; Feb 23, 2006 at 09:06 AM.
Reply
Old Feb 23, 2006 | 09:35 AM
  #15  
subford's Avatar
subford
Fleet Owner
20 Year Member
Photogenic
Photoriffic
Top Answer: 1
Joined: Aug 2005
Posts: 23,668
Likes: 301
From: Easton,Ks
Originally Posted by black58
The light will stop it from charging. On my truck I had the same problem. I hooked up an ammeter and couldn't figure it out. As soon as I spliced the idiot light back on the ammeter jumped to charge. I think I just took the bulb out then. I know it sounds wierd but it worked. John
The QUOTE that you referred to was for a 57 Ford generator system and no it will not effect the charging.

Later when I found out that he had converted it to an Alternator then yes it would keep it from charging.

The generator system does not need the key on or any external power source to charge. The Alternator system however does need an external source to charge.

As an example when I was flying aircraft if you had a dead battery and propped (pulled the engine through with the propeller to start it) the engine to start it you would still have to jump it with the engine running to get it to charge. The engine fires off of a magneto.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
MNchadwick
1973 - 1979 F-100 & Larger F-Series Trucks
11
Dec 4, 2018 09:24 PM
obxairman
Excursion - King of SUVs
18
Jul 14, 2014 01:00 AM
Donutrcng
6.0L Power Stroke Diesel
3
Jun 25, 2009 01:04 PM
punchy1
Electrical Systems/Wiring
11
Nov 30, 2003 04:19 PM
xuare
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
6
Apr 26, 2003 10:37 PM




All times are GMT -5. The time now is 10:45 PM.

story-0
10 Ways Ford is LOSING to the Competition

Slideshow: 10 ways Ford is losing to the competition

By Joe Kucinski | 2026-06-15 09:52:01


VIEW MORE
story-1
Top 6 Best Deals Available on New Fords & Lincolns Right Now

Some great targets in today's expensive world.

By Brett Foote | 2026-06-15 09:35:19


VIEW MORE
story-2
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-3
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-4
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-5
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-6
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-7
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-8
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-9
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE