Problem:

Battery drains in day or 2.

Never used to

i could go a few months no worries. it would always start.

Battery had 3 volts when everything was connected.



What has changed:

i replaced the old cracked worn out stock battery wires with 2 AWG wires.
Cleaned all the wire terminal ends on the starter solenoid.
put some dielectric grease on them.

new battery

what i tried.
i tried an amp draw test and could not see anything bad as far as a draw on the battery when everything in the truck was off and doors closed.

Replaced the battery
the old one would not take a charge.

could a starter solenoid cause a battery drain?

Thanks for the help.

 

if the battery is good and is draining in two days, it will show up when properly tested with an ammeter.
I guess the solenoid could cause a draw if the contacts were partially welded...sending voltage down to the starter (which would be obvious) or sending power to the coil. Either scenario would show BATT+ voltage on the appropriate connection...

 

A bad alternator diode can draw down a battery. I don't have a test other than isolate alt power wire. I know obvious but dome lamp or brake lamps stuck on can do it. You have an underhood lamp and park on an incline? I did that one.

 

I kept having a battery drain and couldn't find it till one NIGHT when I was taking out the trash and saw light coming up through the speaker grate on the dash. Glove box switch failed.

 

Get a test light non LED and pull 1 of the battery cables and put the light between cable and battery.

If the is on you have a draw from something. Dim light little draw bright light big draw.

With the light on pull the fuses 1 at a time till the light goes out. The fuse that makes the light go out is the system you need to check out why the draw.

Now if all fuses are out and still a draw remove the out put wire from the ALT as posted above.
Dave ----

 

Thank you all.
Good suggestions and information.

I will try the suggestions as soon as I get home.

Thank you again

 

Ditto what Dave said, but I will add if you have items that are made to draw constant power i.e. radio with a memory disconnect that first so you don't get a false test

 

Thanks
no radio in the truck yet.

 

I finally got a test lamp and got to testing for the issue.
after trying multiple connections and fuses i narrowed it down to
the alternator and voltage regulator. i pulled the connector
on the voltage regulator and the test lamp no longer is lit up.
i have to charge the new battery before i can proceed.

I already have a new voltage regulator i got when i bought
the truck. i also have a new alternator on order as well.
i got a 1 wire 200 amp. from Bronco graveyard. I wanted
to get the high AMP Alternator because i am eventually going
to get more voltage and amp demanding parts for this truck.
I hope the new alternator from bronco graveyard will be a
good decision.

Thank you all for the helpful information.

 

If it's a one wire alternator that is going in, you won't need an external voltage regulator.

 

Thank you for the information.

i have been researching this and it seems to be a good upgrade.

 

I had the same thing. I just put a switch to turn off the wire from the battery that feeds all the accessories. Problem masked and no battery drain.
Jim
Winnipeg Manitoba Canada

 

This just happened to me after putting in 2 AGM batteries a year ago, and they worked great. 200 amp alternator was put on by the guy that owned it before me. Then one day, it was drained to 4 volts in 4 days of non-use. Charged them up again, and they drained batteries again. Charged it up , 12.4 volts, and started her up, drove out of driveway and the LED volt meter showed 16 volts....Hmmm....never done that ever. Then 17.6 volts. It would go about 16 volts, then any gas-pedal (diesel pedal) and it would jump above 17 volts again. Pulled back in and parked it, and cogitated. Started it up, checked both batteries at idle, 16.3 volts. shut it down. After a couple of hours, I decided that I might as well get the aftermarket voltage regulator (hanging on firewall) info, brand and number (TRANSPO-CN F540XHD-0747-12V). It was so hot I could not hold it with my bare fingers more than 10 seconds. After sitting for hours... I think I found my battery drain. Anyone have a source for the above regulator? An alternator shop in San Marcos TX is supposed to get me one, but I might buy another (like a cam position sensor and a Powertrain relay in the glove box). EDIT: The alternator shop had one, the "Updated number" on the box is 8050-508XHD, but the regulator has TRANSPO-CN F540XHD-27023-12V.