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Keeping the battery charged by running the engine without driving

I won't be able to drive for about 4 months after a knee injury. Can I keep the battery charged by running the engine periodically? If yes, then how often and for how long?
<br/> My transmission is manual (stick) so getting someone I trust to drive it, who has the time, and is willing, is harder than I expected!


  • edited October 2010
    That's bad for many parts of your engine. It would be better to pick up a battery tender (which is pretty cheap) and use that.
  • edited October 2010
    a relatively new battery should hold it's charge for 4 months....reduce your insurance for that period of time.
  • edited October 2010
    Not in a relatively new car. There are several electronic modules in cars now that never power down. In general, the design goal seems to be for the battery to be able to withstand one month.
    I too vote battery tender. Sports Academy sells some good ones (boating section).
  • edited October 2010
    Supplemential information, Do not view your cars charging system as a battery charger, if you break away from the mindset that it is you will on the path of better decisions regarding storing your car
  • edited October 2010
    Additional supplemental information. The old advice was to disconnect the battery during storage. With modern computerized cars this is bad advice, see this link. I also vote for the battery tender.

    And, if this car will be sitting undriven for 4 months, you might want to add a bottle of fuel stabilizer to your gas tank, and drive it a bit to get the stabilizer all the way to the engine before parking it. I have read that current gasoline blends containing ethanol deteriorate faster than gasoline without ethanol.
  • edited October 2010
    A good battery, if fully charged with the cables disconnected will usually rest for 4 months without discharging.
  • edited October 2010
    I also recommend a battery tender. I would also consider checking with your insurance company and eliminate the collision (If you are not driving it, it can't collide with another car.
  • edited October 2010
    The battery should not simply be disconnected, see here.
  • edited October 2010
    Just in case you're wondering what a Battery Tender looks like. The original Battery Tender is a little expensive, but can be left hooked up to the battery for the entire time. I use mine about once a month on one of my older cars to keep the battery topped off. Check out the original Battery Tender or Battery Tender Jr. here.

    You could also purchase a less expensive trickle charger. In my opinion, the Battery Tender is worth the extra cost. It's still cheaper than a new battery.|GRP2005____

    Ed B.
  • edited October 2010
    If the car is parked outside use a solar battery charger. Provides just enough juice to keep the battery up.
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