Notices
Pre-Power Stroke Diesel (7.3L IDI & 6.9L) Diesel Topics Only

Bad Ground?

Thread Tools
 
Search this Thread
 
Old Feb 2, 2010 | 07:49 PM
  #1  
morimoto_87's Avatar
morimoto_87
Thread Starter
|
Senior User
Joined: Aug 2009
Posts: 100
Likes: 0
From: Omaha, NE
Bad Ground?

Every night before i shut my truck off i make sure to charge up my batteries by revving it a little until the voltmeter spikes back to the O and R on NORMAL. When i get it to that point i shut the truck off and if turn the Key On Engine Off the voltmeter reads low...is this because i have a bad ground or do all these truck do this. You all were informing me that i need to clean my grounds anyway which i am going to do this week, but i've been curious if this is the reason?
 
Reply
Old Feb 2, 2010 | 07:57 PM
  #2  
81Bronk36's Avatar
81Bronk36
Senior User
Joined: Nov 2007
Posts: 207
Likes: 0
Check your running and standing battery voltage with a volt meter. What voltage is "O" or "R"??? You should be at 13.5-14.5 running and about 12.6 and up with the truck off.
 
Reply
Old Feb 2, 2010 | 08:22 PM
  #3  
morimoto_87's Avatar
morimoto_87
Thread Starter
|
Senior User
Joined: Aug 2009
Posts: 100
Likes: 0
From: Omaha, NE
I will go out and check it, Thanks for the info!
 
Reply
Old Feb 2, 2010 | 09:37 PM
  #4  
Dave Sponaugle's Avatar
Dave Sponaugle
Post Fiend
Joined: Nov 2003
Posts: 21,285
Likes: 15
From: Nutter Fort, WV
Club FTE Silver Member

You should not have power to the volt meter when the key is off.
If you do, it will be a drain on the battery while not running.
 
Reply
Old Feb 2, 2010 | 09:57 PM
  #5  
81Bronk36's Avatar
81Bronk36
Senior User
Joined: Nov 2007
Posts: 207
Likes: 0
I ment using a multimeter, I believe he was talking about turning his key to the on position.
 
Reply
Old Feb 2, 2010 | 10:29 PM
  #6  
morimoto_87's Avatar
morimoto_87
Thread Starter
|
Senior User
Joined: Aug 2009
Posts: 100
Likes: 0
From: Omaha, NE
I don't have power to the voltmeter with the key off, it's KOEO...And it drops dramatically..i'm running 13.1V running and 11.8V not running. I'm curious if this is because of my bad/dirty grounds.
 
Reply
Old Feb 2, 2010 | 11:24 PM
  #7  
mechelement's Avatar
mechelement
Cargo Master
15 Year Member
Liked
Joined: Oct 2008
Posts: 3,330
Likes: 13
From: Eaton, CO
When you tested it, did you test your volts at your battery terminals? Did you disconnect the two from one another to get a reading from each battery? Do your lights brighten when you hit the skinny pedal and dim when the RPMs fall back to idle? Do your RPMs drop below the set idle speed and then recover to idle? Does your battery seem to drain when your truck sits over night?

I had a slow crank before addressing my corroded terminals, clamps and damaged ground cable. I bought a battery terminal & terminal clamp shaver and scrubber for a few bucks from a parts store to get clean contact again. Clean everything up really good, coat everything liberally with dielectric grease and reinstall.
 
Reply
Old Feb 3, 2010 | 05:44 PM
  #8  
9473's Avatar
9473
Senior User
Joined: Nov 2009
Posts: 255
Likes: 1
Originally Posted by morimoto_87
I don't have power to the voltmeter with the key off, it's KOEO...And it drops dramatically..i'm running 13.1V running and 11.8V not running. I'm curious if this is because of my bad/dirty grounds.
It is possible that one of your batteries is going. Have you checked the water level in them? To check the voltage disconnect the connection between the two and check the voltage of each. They should be the same or very close. If you do have a bad one then to replace as a set is best. Good luck.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-1

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

 Brett Foote
story-2

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

 Michael S. Palmer
story-3

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

 Verdad Gallardo
story-4

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-5

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

 Brett Foote
story-6

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

 Michael S. Palmer
story-7

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
story-8

Top 10 Ford Trucks Coming to Mecum Indy 2026

 Brett Foote
story-9

5 Best / 5 Worst Ford Truck Wheels of All Time

 Joe Kucinski
Old Feb 3, 2010 | 07:06 PM
  #9  
81Bronk36's Avatar
81Bronk36
Senior User
Joined: Nov 2007
Posts: 207
Likes: 0
Originally Posted by morimoto_87
I don't have power to the voltmeter with the key off, it's KOEO...And it drops dramatically..i'm running 13.1V running and 11.8V not running. I'm curious if this is because of my bad/dirty grounds.
Ya thats bad, I would check all your cables and clean your block grounding points
 
Reply
Old Feb 3, 2010 | 07:25 PM
  #10  
starmilt's Avatar
starmilt
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
Even a bad battery can show the same or very close voltage unless you load test them then the bad one will show quick. if you don't have a load tester, most parts houses will do it for you free of charge if you disconnect the cables.

The same applies to the alternator checking with a volt meter gives you an idea but only measures the volts it is putting out not the amps. It is very possible for it to be putting out 13.5 volts and only 5 amps so it would fully charge your batteries in a couple years.
 
Reply
Old Feb 3, 2010 | 07:41 PM
  #11  
9473's Avatar
9473
Senior User
Joined: Nov 2009
Posts: 255
Likes: 1
Originally Posted by starmilt
Even a bad battery can show the same or very close voltage unless you load test them then the bad one will show quick. if you don't have a load tester, most parts houses will do it for you free of charge if you disconnect the cables.

The same applies to the alternator checking with a volt meter gives you an idea but only measures the volts it is putting out not the amps. It is very possible for it to be putting out 13.5 volts and only 5 amps so it would fully charge your batteries in a couple years.
Probably so but every time I've had starting issues traced to the batteries the difference in voltage has been noticeable like 11.8 or 9 compared to 12.6 or 7. And although they might show they're charging the charge won't take. And at least for off grid 12V applications the voltage should be checked from 8 to 24 hours after a charge or discharge. More accurate to check the specific gravity.
 
Reply
Old Feb 3, 2010 | 07:48 PM
  #12  
starmilt's Avatar
starmilt
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
I hear you but like I said they can still show close if they don't, there is one of two things going on one battery is bad or the cable between them is bad or the ground on the bad one is bad not letting the alternator fully charge it. Then again they both have to be fully charged for the load test to work.

Are you off grid, if so how do you like it.
 
Reply
Old Feb 3, 2010 | 08:35 PM
  #13  
9473's Avatar
9473
Senior User
Joined: Nov 2009
Posts: 255
Likes: 1
Originally Posted by starmilt
Are you off grid, if so how do you like it.
It's a work in progress but I really enjoy the challenge, even the chopping wood Not able to get to it generally anywhere from early Dec. to early May. Short growing season, lost the garden first week of Sept. last year. I pushed it last spring going in the second week of April and if I would have known you guys then I would have taken some pics pulling the old girl through three feet of snow. The winch got less of a workout than I did though lol. If you see my summertime pic that's the view looking out the front.
 
Reply
Old Feb 3, 2010 | 08:48 PM
  #14  
starmilt's Avatar
starmilt
Post Fiend
Joined: Oct 2007
Posts: 10,501
Likes: 5
From: Faibanks Ak.
Where is the summertime pic. IIRC you are in northern bc or am I thinking about someone else.
 
Reply
Old Feb 3, 2010 | 09:04 PM
  #15  
morimoto_87's Avatar
morimoto_87
Thread Starter
|
Senior User
Joined: Aug 2009
Posts: 100
Likes: 0
From: Omaha, NE
I have two brand new 850 CCA motorcraft batteries, so i'm gonna clean my terminals and grounds and post back. Thanks all!
 
Reply



All times are GMT -5. The time now is 05:29 PM.

story-0
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

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


VIEW MORE
story-1
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-2
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-3
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-4
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-5
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-6
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
story-7
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-8
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-9
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE