Keep Killing Batery

[98MagnumDakota]

Got a 85 D100 with the 360, was originally a 318 but original own changed it out. Took the truck out this spring an it ran ok but the radio and lights would flicker. We just figured it was a ground issue. Took it to the dragstrip an the altenator died, that was a fun ride home in the dark with no head lights. Put the new altenator in an it fix the problem we thought was a ground. All was good till the other day when it all happened again. what is this anybody know?

[ramitupurs84]

Shorts or corroded ends?

[98MagnumDakota]

Ends are good its some were else.

[acton mike]

check the cables carefully; they can corrode from the inside while still looking solid on the outside

You need to run a diagnostic on your charging system; you need to check for volts and amps output

The check the connector plugs where the harnesses go through the firewall into the cab and then have a good look at the wiring to and from the ammeter in the dash

[ramitupurs84]

Mike, wouldn't the wires have small buldges in the plastic shroudaround the wires.

I have expierenced corroded bulk head connectors deep inside were the pins pertrude. Could that be a area to check as well?

[98MagnumDakota]

Ill, double check but Im almost positive it isnt a corosion issue. Working on checking the charging system, how many amps am I looking for. Im just hopping someone can point out a possible trouble spot on this system.

[B-300]

Since it ran home without lights the problem must be were power branches to the light switch... The engine had to be getting power from the battery and/or alternator.
High resistance in the charging circuit will cause the regulator to cycle on an off which is probably why your lights flickered. A bad battery will also cause problems more so as the night gets cooler.
I agree with the others about the bulkhead connector and ammeter.
Use a voltmeter and measure the voltage drop in the charging system from battery + to the large terminal on the alternator. It should read zero with the engine off and not more than 0.3volts with the engine running and the headlights on... less with the lights off.

[98MagnumDakota]

We had to jump start it twice, it would stay runinng while going down the road but when you come off the peddle an on the clutch it would stall. Also while driving if you would get on it while driving it would spit a sputter so it didnt have much spark power either.

[B-300]

It sounds as if it's not charging and the battery is low.
The battery should be at 12.6 volts when charged and allowed to rest. When the truck is running the charging system should increase the battery voltage to about 14 volts... This depends on the temperature so 13.5 to 14.5 is good.
It's possible the battery is bad. They tend to fail in cold and hot weather and I know there is a heatwave in the east coast. A bad battery can also kill an alternator because it attempts to charge and spikes the voltage up and down. The spikes will burn out the diodes (rectifiers).... The alternator has 3 phases, if one goes out it can only charge at 2/3's capacity.

[98MagnumDakota]

Changed The voltage reg. and so far so good. But I think it was changed on the truck before so there could be another problem else were.

[mojavemark]

I had a simular problem, change the altonator, voltage regulator, battery cables, and a bunch of other stuff. Still had problems.
Because the battery held a charge I assumed it was good. Had it tested, it showed a shorted cell. Put a new battery in and haven't had a charging problem in 5 years. A bad battery will cause a bunch of problems on these Dodge charging systems.

[98MagnumDakota]

I figured that was the case with my old battery so I swaped it out with one I had in another truck an still had the problem. (The other truck was running fine except I blew the motor a few days prior but it had no charging issues.