Battery loses charge

I replaced the Gill battery two months ago when I purchased my C172. Now the new battery loses its charge overnight, so it needs to be charged in order to start the engine. With the battery disconnected there is infinite resistance between the circuit terminals (master and radio master switches off). With the battery connected to an ammeter in the circuit, there is no detectable current flowing in the circuit (switches off). The 2-month-old battery has two cells with low specific gravity. I don't understand what is causing this.

Comments

  • Scott ShererScott Sherer COO Forum Moderator

    Stand by while I send this to our A&P Erich Rempert.

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Cessna Owners Organization Forum Moderator and Cessna Owners Author.

    Need help? Let me know!

  • Scott ShererScott Sherer COO Forum Moderator

    Here's a response from our A&P Erich Rempert:

    It's a Gill battery, that's the cause.

    Of course, that's overgenerallized and not fair but I have found endless problems with wet batteries (Gill is the most common) as they are sold and shipped dry and need proper activation, load testing, top charging, and periodic maintenance to be airworthy. If this is not properly accomplished it can damage the new battery and reduce its performance permanently.

    AGM batteries like the Concorde are usually airworthy out of the box and have more cranking amps and a higher amp/hr rating than their wet counterparts. They also last substantially longer and require very little maintenance.

    You will need to see if you can revive your battery by adjusting the electrolyte levels and charging per the manual, if the battery does not come back it will need replacement. (I suggest a Concorde and a Battery MINDER that will constantly desulfate your plates and keep your investment healthy for years to come). [Battery MINDER for Concorde and Gill are different units as AGM asnd Wet batteries have different charging requirements so keep this in mind when you buy].

    After you have a good battery to work with take a digital multi meter and connect it in series with the circuit and see if you have a draw. Courtesy lighting and clock keep alive circuits are often hot at all times. There are typically fuses adjacent to the battery for these items, if present removing their respective fuses will eliminate the draw.

    With a good battery and a Battery MINDER you should be able to leave those fuses as they are and have plenty of power. Which leads me back to the Gill battery and it's common issues associated with it's activation and maintenance that often cause problems sometimes "right out of the box"...

    I have seen good Gill batteries, but they take a lot of labor, so in the long run the Concorde is also less expensive...

    ~Erich Rempert, IA Consultant

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Cessna Owners Organization Forum Moderator and Cessna Owners Author.

    Need help? Let me know!

  • Thanks Erich for the insights!

  • Scott ShererScott Sherer COO Forum Moderator

    Erich is awesome... a walking and talking encyclopedia of aviation knowledge...

    Scott Sherer
    Wright Brothers Master Pilot, FAA Commercial Pilot
    Aviation Director, Cessna Owners Organization Forum Moderator and Cessna Owners Author.

    Need help? Let me know!

Sign In or Register to comment.