battery looses charge

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battery looses charge

August 14, 2009, 12:00:43 PM

when the car is running the battery is getting charged and it can run all day. if i shut the car off and disconnect the battery i can reconnect then start again. if i let the car sit for say 5-10 mins with the battery connected it will be completely dead when i go to start it again.
any thoughts guys?

battery looses charge

Reply #1 – August 14, 2009, 01:29:08 PM

check the water in the battery, also if the car has an external voltage regulator it could be sticking and should be replaced.

battery looses charge

Reply #2 – August 14, 2009, 02:11:12 PM

If you leave the battery disconnected overnight is it still good?
If you have a meter, check the battery voltage with it disconnected. Does it hold at 12.5 volts?

5 to 10 minutes is a very severe discharge rate if the battery is good.

To see if you have a battery drain, disconnect the negative battery cable. Hook a 12v test light between the negative cable and the negative battery post. If it lights you have a drain.
Make sure nothing is "on" in the car. Doors shut (dome light off), under the hood light (take the bulb out) ect.
Then it's a matter of disconnecting stuff until the light goes out.

You can get a test light at an auto parts store.
Some hardware stores have them but make sure get 12v light. They also carry electricians 110/220 volt test lights.

battery looses charge

Reply #3 – August 14, 2009, 02:16:15 PM

Quote from: 88turbo;286649

check the water in the battery, also if the car has an external voltage regulator it could be sticking and should be replaced.

Don't know why an external regulator would be more apt to "stick" than an internal one.
Unless you are thinking way back to when they were a mechanical device with relays.

battery looses charge

Reply #4 – August 14, 2009, 03:47:58 PM

What if you unhook the main charge wire/wires from the alternator does it still drain the BAtt? If not sounds like maybe the alt has an internal short. Seen it more than a few times.

stuckman

battery looses charge

Reply #5 – August 14, 2009, 04:01:04 PM

I'm thinking back to the relay box that bolts to the fenderwell before they went to the internal regulator. I had similar problems with my cougar.

battery looses charge

Reply #6 – August 14, 2009, 05:42:00 PM

Quote from: 88turbo;286663

I'm thinking back to the relay box that bolts to the fenderwell before they went to the internal regulator. I had similar problems with my cougar.

I think you have to go back to the 50's to find a relay type regulator.
Your external reg was the same as your internal one, technology wise.

battery looses charge

Reply #7 – August 14, 2009, 10:23:48 PM

Quote from: softtouch;286680

I think you have to go back to the 50's to find a relay type regulator.
Your external reg was the same as your internal one, technology wise.

Nope you don't have to Go back to the 50's you just gotta buy parts from the 50's! I know this I sold one just last week. We keep them in stock still pricey $63! Had to listen to the old guy tell me how you could adjust and tune those to make the gen to make the power they wanted. Then had to listen to him complain about the price of it! They do kinda look like the ones from the external regulator days in ford but those relay type are about twice as TALL. Then no plug in all hard wired to the unit and bolted down onto it.

Stuckman

battery looses charge

Reply #8 – August 15, 2009, 05:44:37 PM

Most likely a short internal to the alt. To verify, unplug the alt connector and leave the battery hooked up and give it the ten minutes to see if it will start.

battery looses charge

Reply #9 – August 17, 2009, 10:11:54 AM

To settle the voltage regulator debate, Ford used only electro-mechanical regulators thru 1977, and a few models still used them in '78... I believe Chrysler was first to use a solid state regulator in the early 70s, not real familiar with those foreign cars...

Was mid 80s before Ford started using alternators with internal regulators...

battery looses charge

Reply #10 – August 31, 2009, 01:30:46 AM

if the alternator had something wrong with it then wouldnt that prevent it from charging the car while running?
i think when i hooked everything up after the first time i had it apart i may have hooked up the cables on the alt wrong. would that have hurt anything inside of it possibly?
still workin around to getting a test light too

battery looses charge

Reply #11 – August 31, 2009, 01:39:54 AM

btw yea its not the battery i have been disconnecting it and it stays charged

battery looses charge

Reply #12 – August 31, 2009, 01:31:50 PM

ok so i disconnected the alternator and the draw is still there. When i hook it back up and run the car im geting around 14-15 volts. where do i go from here just start disconnecting things and watch the multimeter?

battery looses charge

Reply #13 – September 02, 2009, 11:42:05 PM

well i decided im going to pull the motor/trans out before winter so i can get the 2nd gear fixed and rebuild the motor so i guess ill have to address this problem later. can i still find the short with the motor out or not?
thanks
dan

battery looses charge

Reply #14 – September 03, 2009, 12:59:50 AM

Quote from: croga001;289120

ok so i disconnected the alternator and the draw is still there. When i hook it back up and run the car im geting around 14-15 volts. where do i go from here just start disconnecting things and watch the multimeter?

disconnect disconnect all secondary wiring from the starter relay.
light goes out? if yes.............(should be your only answer)

then.........
one by one, touch each wire to the starter solenoid.
when the light comes back on, ID the wire color and report back.

get your test light over on the pos batt cable.