Alternator current draw

[AL in NY]

Went out to warmup my 30 pickup before the storm today, and the battery was totally dead. Battery was new this spring and I've never had any cold weather starting problems before. I replaced my generator with a Russ Evans one wire alternator this summer. Do these types of alternators have a slight current draw on the battery all the time? It has been about 5 weeks since I started her up.

[spdway1]

There is a storm coming?
By the TV, you would think the world is going to end

I have not had my A P/U started in 2 Months

Sorry I can not help you out on the "Draw"

[Kevin in NJ]

Some versions of one wire alternators will draw a current when not running.

[BILL WILLIAMSON]

Originally Posted by Kevin in NJ

Some versions of one wire alternators will draw a current when not running.

Kevin,
Not sure about some alternators having a draw??? BUT, on Minerva, with a 6 volt positive ground, 1 wire alternator, she sat for 4 months while I was hospitalized & in re-hab. With a 6 year old battery, NO trickle charger or "tender", she fired off as if she had been run just yesterday!! I only once, EVER, charged her battery in 8 years & that was when I had a "brain-fart" & left the dash light ON!!
The alternator was a NEW one, converted to 6 Volts, from a supplier that used to be in Redding, Ca. (Forgot their name??) Bill W.

[Herb Concord Ca]

Yes, both of my one-wire 6V positive ground alternators have a draw on the battery. Mine were about 120ma. Enough to flatten the battery in about 4-5 days (in my case).

This got me in the habit of removing the starter mounted fuse when I knew I would not start the A for a few days or longer, overnight way no problem.

[RonC]

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Just pull your fuse or install a disconnect on your battery. It's not good practice to leave your A for weeks or months with power in your wiring. Many disconnect the power always

[jmeckel]

I have a new alt. On mine and there is not any noticable drain. My A sat for 2 months this fall without being started, after I broke my back. No charger or maintainer and it started right up. If you have a 120ma drain there is something wrong, possiblely a diode problem in the alternator. Or a resitive short some place else.

[Tom Wesenberg]

If I were to use an alternator (it will NEVER happen) I would put a switch or fuse in the circuit to disconnect it when it's parked.

[Barry B./ Ma.]

I had that happen once, a small draw from the alternator will kill the battery overnight. The supplier gave me another alternator and had no problem after that, he said it could have been a bad diode.
I installed a shutoff switch and always turn it off when unattended, you never know when a short can develop especially with mice running around.

[jrelliott]

Yes, there is a small current drain in the one wire and 3 wire alternators as this is how the fields get energized. There is little residual magnetism in the fields of an alternator the way there is in a generator. That is the reason a generator will produce electricity when the battery is dead and can push start it. You cannot push start a vehicle with an alternator and a dead battery to get it started. The fuse or a disconnect is the way to go with an alternator and adds just a safety factor. JMHO

[Patrick L.]

I've not seen an alternator that didn't draw. Some draw more than others, but, none should draw enough to flatten a battery is just a few days or a month.
That said, there was/is a recent post about a main disconnect as a bandaid. A main disconnect or fuse is kind of a good thing for more than one reason, this is a good one.

[AL in NY]

Thanks Guys, when the weather warms up a bit I'll go out and measurement the current draw of my alternator and report back. Hopefully that's the problem. I'm also going put a 30 amp toggle switch in series with the main fuse to alleviate my battery from going dead during long term storage.