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

Battery drains completely down

Thread Tools
 
Search this Thread
 
Old Mar 22, 2014 | 09:51 AM
  #1  
abeagle's Avatar
abeagle
Thread Starter
|
Senior User
Joined: Sep 2013
Posts: 269
Likes: 2
From: Abingdon. VA
Battery drains completely down

I have a problem with the battery draining completely down every few weeks. I have tried to do a thread search but could not readily find a thread that fits 50s F100s. If there is then let me know or any ideas?

It is a fairly new good quality ORielly battery. The truck runs and starts fine. Then out of the blue it will not start (even the same day or trip) and the battery drains. I check with volt multimeter and it is down all the way. A full charge from the handheld charger/jumpstarter brings it back, but I never know when it will go down again. Most all of truck is old, stock, except for 12 volt upgrade.

I am far from proficient as a mechanic, especially with electricals but I have checked what I can and have found no drains. Ever use a battery float charger or some type of battery saver on your 12 v truck that I could use until I better determine what might be the cause? Any idea on what could be the cause? It is frustrating and my wife is getting gun shy about going out in the truck.
 
Reply
Old Mar 22, 2014 | 10:38 AM
  #2  
rhopper's Avatar
rhopper
Fleet Mechanic
Joined: Mar 2005
Posts: 1,511
Likes: 1
From: peyton, colorado
Club FTE Silver Member

You'd have to have a big parasitic drain for it to go dead in the time frame of one trip, or even one day. I doubt that's your problem. I've had a few batteries fail in my life, and most had symptoms like yours. They work fine after a jump, test fine when charged, then fail randomly. Charge or jump them, and the cycle repeats. I've had both old and new batteries do this.
 
Reply
Old Mar 22, 2014 | 10:44 AM
  #3  
ALBUQ F-1's Avatar
ALBUQ F-1
Fleet Owner
20 Year Member
Liked
Loved
Community Favorite
Joined: Jul 2004
Posts: 27,294
Likes: 1,055
From: NM
Are you using a generator or an alternator for the 12v conversion? My first suspicion would be the battery too, especially since it is still fairly cold out. A weak or old battery will die when it's cold.
 
Reply
Old Mar 22, 2014 | 10:45 AM
  #4  
Tedster9's Avatar
Tedster9
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
If there is a large drain as suspected a float charger will choke. Better to disconnect the battery and keep it charged that way until it's remedied. Auto start batteries do not take a total drain even once, very well.

How are you testing for drain? With your amp meter in series with a disconnected battery cable and post there should be very little current flow, less than half an amp.
 
Reply
Old Mar 22, 2014 | 10:55 AM
  #5  
FortyNiner's Avatar
FortyNiner
Logistics Pro
10 Year Member
Liked
Loved
Community Favorite
Joined: Jun 2011
Posts: 4,995
Likes: 422
From: u-rah-rah Wisconsin
Check your connections first. Then run down the source of the drain: ignition switch, generator/alternator not charging, bad battery. Personally, I doubt the battery is bad and expect the charging system. While you figure it out, get a portable booster unit and carry it in the truck. This will allow you to jump start on your own.

Use the auto parts guys to check the generator/alternator function. They can also verify on battery function.
 
Reply
Old Mar 22, 2014 | 11:18 AM
  #6  
oldmerc's Avatar
oldmerc
oldmerc
Joined: Jul 2011
Posts: 1,538
Likes: 5
From: Edmonton,Alberta
Club FTE Gold Member
I would suggest you go to your fuse panel and start pulling one fuse at a time and place the probes of a digital VOM set at the 10 Amp setting on the fuse contacts to isolate the circuit that is causing the possible drain on the battery . Also test the voltage across the battery terminals while the engine is running to see if the alternator is putting out enough voltage to properly charge the battery .
 
Reply
Old Mar 22, 2014 | 11:43 AM
  #7  
dmack91's Avatar
dmack91
Elder User
Joined: Feb 2012
Posts: 948
Likes: 0
From: Central Oregon
If you have a multimeter, an easy first check is to see where the battery charge is when it is not running. The battery should be around 12.5 volts. When running with a good charging system, it should be between 13.4 and 15.3 volts generally. Sometimes, you have to have the engine running above idle before the charging system kicks in.
 
Reply
Old Mar 22, 2014 | 12:30 PM
  #8  
Jolly Roger Joe's Avatar
Jolly Roger Joe
Lead Driver
Joined: Jul 2011
Posts: 6,599
Likes: 34
From: Rockingham, VA
Originally Posted by dmack91
If you have a multimeter, an easy first check is to see where the battery charge is when it is not running. The battery should be around 12.5 volts. When running with a good charging system, it should be between 13.4 and 15.3 volts generally. Sometimes, you have to have the engine running above idle before the charging system kicks in.
And along with everything that's been said, where is your voltage regulator? Do you have a generator or alternator? As said, maybe the battery isn't always being charged while it's running.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

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

 Verdad Gallardo
story-1

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-2

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
story-3

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-4

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-5

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-6

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-7

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-8

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-9

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
Old Mar 22, 2014 | 02:33 PM
  #9  
Steves55's Avatar
Steves55
Tuned
15 Year Member
Joined: Apr 2010
Posts: 366
Likes: 3
Originally Posted by Jolly Roger Joe
And along with everything that's been said, where is your voltage regulator? Do you have a generator or alternator? As said, maybe the battery isn't always being charged while it's running.
A faulty voltage regulator was draining my battery on my 46 Ford car.
 
Reply
Old Mar 22, 2014 | 02:39 PM
  #10  
CharlieLed's Avatar
CharlieLed
Lead Driver
15 Year Member
Liked
Loved
Community Favorite
Joined: Aug 2006
Posts: 8,093
Likes: 652
From: Brentwood, TN
Club FTE Gold Member
Something is pulling current from the battery when the engine is not running. One of the quickest/easiest tricks I use is to loosen the battery terminal (+ or -) and see if it sparks when the terminal connection pulls away from the post. When there is something drawing current in the system there will always be a spark when you disconnect the battery terminal and touch it back again. Use oldmerc's technique if you find that there is a draw in the system.

I once had a Cadillac Eldorado that had a battery that would drain down...the battery was good but it kept draining down. I pulled every fuse until I found the circuit that was active...it was the light in the glovebox! Were it not for a good troubleshooting procedure I would have NEVER found that problem.
 
Reply
Old Mar 22, 2014 | 02:53 PM
  #11  
raytasch's Avatar
raytasch
Believe Nothing
20 Year Member
Joined: Jun 2004
Posts: 7,514
Likes: 398
From: W. Central FL.
Club FTE Silver Member

And, don't overlook a sticking or corroded brake switch.
 
Reply
Old Mar 22, 2014 | 03:58 PM
  #12  
abeagle's Avatar
abeagle
Thread Starter
|
Senior User
Joined: Sep 2013
Posts: 269
Likes: 2
From: Abingdon. VA
Thanks for all the posts. I am going to make a list of possibilities and options and try to work thru them. Wished I was better at electrical.

I have an alternator with the 12 v conversion. The truck is old stock and no dome, glove, or other interior light other than instruments.

My multimeter shows about 12.5 v (engine off and no switches on) after about a 5 hr charge yesterday. After a 15 or 20 minute drive thru town a little while ago the multimeter showed about 11.5 v. I wonder if what seems a quick dieoff is really the overall charge finally getting too low or something else.

I'm not sure how to check the key ignition switch, but it is a little wobbly with the key in - but from the posts it seems it could be most everything. Doesn't seem it will be a quick fix unless luck gives a solution at the first.

Keep the possibilities and what to do coming. Will keep the portable battery charger/jumpstarter in the truck. I'm not going to stop driving it since several grandkids are coming into town next week unless it gets dangerous or quits running.

Keep the idea list coming - something will hit.
 
Reply
Old Mar 22, 2014 | 04:08 PM
  #13  
Wayne Waldrep's Avatar
Wayne Waldrep
Elder User
Joined: Aug 2012
Posts: 751
Likes: 0
From: Cuba, AL (NO internet)
If you had 12v and you drove a while then had less, I'd go for alternator not charging first. Just my 2 cents....worth about .5v
 
Reply
Old Mar 22, 2014 | 04:11 PM
  #14  
abeagle's Avatar
abeagle
Thread Starter
|
Senior User
Joined: Sep 2013
Posts: 269
Likes: 2
From: Abingdon. VA
If the alternator was not charging, would the engine die while running? It seems to run fine once started and idling well.
 
Reply
Old Mar 22, 2014 | 04:14 PM
  #15  
Jolly Roger Joe's Avatar
Jolly Roger Joe
Lead Driver
Joined: Jul 2011
Posts: 6,599
Likes: 34
From: Rockingham, VA
Originally Posted by abeagle
If the alternator was not charging, would the engine die while running? It seems to run fine once started and idling well.
As someone already mentioned in a previous post, you should check the battery voltage while the truck is running. You should be able to see it charging and discharging as the regulator regulates it.
 
Reply



All times are GMT -5. The time now is 05:46 PM.

story-0
Rezvani's Latest Post-Apocalytic 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 | 2026-05-30 18:33:59


VIEW MORE
story-1
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-2
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-3
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-4
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-5
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-6
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-7
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-8
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-9
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE