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bad ground problem....I think.

  • Thread starter Thread starter Car RamRod
  • Start date Start date Aug 30, 2005

Car RamRod

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Mar 30, 2005
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Aug 30, 2005
#1
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  • #1
My car isnt holding a charge. The alternator is new, and the battery isnt new, but isnt old. Can anybody give me some tips on finding the problem?
 

garystocker

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Aug 30, 2005
#2
  • Aug 30, 2005
  • #2
Buy a new battery make it a die hard

listen. Batteries last 5 years if they are a good brand.
Cheapies last 2 years.

If your voltmeter reads that a charge is produces but not retained...it can only be the battery. (Obviously make sure the connections are clean, sanded, corrosive spray, new pos & neg cable could not hurt.

I would start with a new QUALITY battery and ford battery cables.

I would be interested in knowing how you make out. Let mw know if you find out more.

gary
 

garystocker

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#3
  • Aug 30, 2005
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Did the problem start with the installation of the new alternator? It could be the voltage regulator...but the voltmeter tells all...what does it read??
 

Car RamRod

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#4
  • Aug 30, 2005
  • #4
no, the problem existed before that.

I will probably be mounting my battery in the trunk in a few weeks, but first I want to get this deal straigtened out. I might just go with an optima battery and see if it helps.....If im correct, I want the yellow top optima right?

Thanks for the quick responses.
 

jrichker

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garystocker said:
Did the problem start with the installation of the new alternator? It could be the voltage regulator...but the voltmeter tells all...what does it read??
Click to expand...
The voltage regulator on 86 and later model years are built into the alternator.

See http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for more infor & wiring diagrams
 

garystocker

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If the problem existed before the alternator it cannot be the voltage regulator as they come as a unit...

More proof it is a battery. Any quality battery you like will work. I have never purchased an optima but I hear good things about them. what does one cost>?
 
D

dwhiskie

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Sep 18, 2004
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Aug 30, 2005
#7
  • Aug 30, 2005
  • #7
garystocker said:
If the problem existed before the alternator it cannot be the voltage regulator as they come as a unit...

More proof it is a battery. Any quality battery you like will work. I have never purchased an optima but I hear good things about them. what does one cost>?
Click to expand...
I got a optima red and paid 104.00
 

bubba-dough

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Dec 28, 2004
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Aug 30, 2005
#8
  • Aug 30, 2005
  • #8
garystocker said:
listen. Batteries last 5 years if they are a good brand.
Cheapies last 2 years.

If your voltmeter reads that a charge is produces but not retained...it can only be the battery. (Obviously make sure the connections are clean, sanded, corrosive spray, new pos & neg cable could not hurt.

I would start with a new QUALITY battery and ford battery cables.

I would be interested in knowing how you make out. Let mw know if you find out more.

gary
Click to expand...

Definately get new "quality" cables. I had a problem a year or so ago and finally changed cables and the problem was solved.
 

Car RamRod

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Mar 30, 2005
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Aug 30, 2005
#9
  • Aug 30, 2005
  • #9
Ill check over the terminals and those small things, but Im gonna try not to buy new ones of those considering Im changing the setup fairly soon. I think Ill just go down to sears and get a die-hard battery. I know I should get an optima, but Im not sure that I really need that good a battery. Ill let you all know how it works out.
Thanks for the help.
 

Car RamRod

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#10
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Im pretty sure Ill go with this battery. Ill see what my father says when he gets home. What do you think?
http://www.sears.com/sr/javasr/sear...arget=Subcategory&subcat=Automotive+Batteries
again, thanks alot
 

HISSIN50

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#11
  • Aug 30, 2005
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I dont know exactly what 'holding a charge' means, but you could have an issue like a short/battery drain.

As mentioned, if the voltage at the alt is more than ~.5 volts more than at the battery or solenoid, there is a drop occuring. And if you have a 3G, doing JR's ground upgrade is a must.

Good luck bud.
 

jrichker

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Here's some advice for your future plans...

Rear mounted battery ground wiring. Follow this plan and you will have zero ground problems.

One 1 gauge or 1/0 gauge wire from battery negative post to a clean shiny spot on the chassis near the battery. Use a 5/16” bolt and bolt it down to make the rear ground. Use a 1 gauge or 1/0 gauge wire from the rear ground bolt to a clean shiny spot on the block.

One 4 gauge wire from the block where you connected the battery ground wire to the chassis ground where the battery was mounted up front. Use a 5/16” bolt and bolt down the 4 gauge engine to chassis ground, make sure that it the metal around the bolt is clean & shiny. This is the alternator power ground.

Crimp or even better, solder the lugs on the all the wire. The local auto stereo shop will have them if the auto parts store doesn't. Use some heat shrink tubing to cover the lugs and make things look nice.

The computer has a dedicated power ground wire with a cylindrical quick connect (about 2 ½”long by 1” diameter. It comes out of the wiring harness near the ignition coil & starter solenoid (or relay). Be sure to bolt it to the chassis ground in the same place as you bolted the alternator power ground. This is an absolute don’t overlook it item for EFI cars
 

Car RamRod

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#13
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ok well I went around the engine compt. and cleaned and tightened the grounds, starter cable, and a few other misc things. I also put a new terminal on the neg. side of the battery because the old one was shot. I know my battery isnt so good, I just want to have everything else working right before I put in a new battery.

thanks jricker, I will definetly be doing some searching before I do my battery to trunk move.
Thanks again guys
 

tmoss

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Jun 28, 2001
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Aug 31, 2005
#14
  • Aug 31, 2005
  • #14
When I removed my negative cable bolt from my timing cover, the threads in the timing cover were corroded to hell due to galvanic corrosion (two metals - aluminum timing cover and steel bolt). I was having a slow crank condition when the engine was hot (expanded aluminum). I relocated the ground to the driver's head and no problems since.

Don't overlook this as a possibility.
 

Hissing Cobra

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Aug 31, 2005
#15
  • Aug 31, 2005
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I have mine grounded to the engine block itself (passenger side front near the bottom of the block.) Also make sure that you have a grounding strap from the back of the engine block to the firewall. As for your battery, try another one if possible. Your volt guage should be reading 14 volts (13 if you have underdrive pulleys) at idle. If it's not then you may have a faulty alternator/regulator (even if they're new.) If the battery cables are gone they're fairly cheap (less than $20.00 for AutoZone units) and this could be a cheap alternative until you relocate your battery.

Good luck!
 
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