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[email protected] tabbypurr@gmail.com is offline
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Default Engine run time to keep battery charged

On Wednesday, 6 February 2019 16:44:51 UTC, wrote:
On Wednesday, February 6, 2019 at 11:09:24 AM UTC-5, tabby wrote:


If it's below freezing the air is bone dry & any water from combustion frozen solid. Regardless of temperature cars do not need running every 2 weeks unless electrically faulty.


Water in the air is not the issue, and never was. Water from products-of-combustion are the issue.


I've not heard any reason they wold be, nor how running every 2 weeks would cause less of that than every 4.


Ideally, the battery would be float-charged with an actual "smart" charger. Most of the Chinese Junque chargers these days run a continuous charge into the battery - AKA a "trickle" charger. Not hardly the same thing. A trickle charge will either:

a) Destroy the battery by charging faster than the self-discharge rate.
b) Allow the battery to run flat by charging slower than the self-discharge rate.
c) Miraculously match the self-discharge rate... odds of this?

A Float Charger will activate at some point when the battery charge drops below the trigger level, charge to a specific set-point, and then shut off until the next cycle.

Failing the availability of a float charger, and, especially in extreme (hot or cold) weather conditions, "about every two weeks" is a good rule-of-thumb. One never quite knows the actual condition of the battery, charging system, parasitic loads and so forth, so 'designing to the specific need' may not be ideal. And more than a month or so starts getting into the risk of seals drying out - especially in 30+ year old engines.

Peter Wieck
Melrose Park, PA


I presumed the OP didn't have a charger, or we wouldn't be having this discussion. If the OP does have a decent charger, use it. If a not-decent charger, don't.


NT