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Hey there.
My 75 Power Wagon sits most of the time. I use it to haul junk and landscaping waste for trips to the dump.
The truck has a 440 and a stock ignition and charging system. When running, it charges fine but after sitting a couple weeks, the battery is too discharged to start the engine.
At first I suspected a weak battery but I switched to another one and it also discharges. I’ve resorted to pulling the positive cable from the battery after parking it.
I mentioned this on the truck forum and one member blamed the alternator. I admit to not knowing as much about electrical systems as I do about other things. To me, if an alternator is charging, it is okay.
Is that wrong?
Can an alternator actually discharge a battery with the engine off ?
My 75 Power Wagon sits most of the time. I use it to haul junk and landscaping waste for trips to the dump.
The truck has a 440 and a stock ignition and charging system. When running, it charges fine but after sitting a couple weeks, the battery is too discharged to start the engine.
At first I suspected a weak battery but I switched to another one and it also discharges. I’ve resorted to pulling the positive cable from the battery after parking it.
I mentioned this on the truck forum and one member blamed the alternator. I admit to not knowing as much about electrical systems as I do about other things. To me, if an alternator is charging, it is okay.
Is that wrong?
Can an alternator actually discharge a battery with the engine off ?
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