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wapsijim

JD LA135 Battery issue

wapsijim
11 years ago

I have John Deere LA135 that I use to cut my 2/3 acre lawn, nothing to difficult other than this years drought... My problem is the battery on the mower won't charge or stay charged. I've had the battery checked and the guys at Autozone say it's good. I charge it up every second or third time I mow, but it won't charge up running the mower? Any ideas or where should I look first?

thanks

Comments (4)

  • bill_kapaun
    11 years ago

    I guess it's time to test the charging system-

    It appears you have some version of a Briggs engine with a 9 AMP charging system.
    Post the actual engine Model & TYPE #'s. It might help--

    The stator can be tested.
    Disconnect the 3 wire connector to the Voltage regulator on the engine.
    It should be 2 YELLOW Wires and 1 RED.

    The output between the 2 YELLOW wires should be either 28 or 40 Volts AC MINIMUM at HIGH engine speed.

    I'm not sure which is correct for your tractor, but if you are getting less than 28 VAC, the stator is bad in either case.
    Since yours is supposedly a 9 AMP, I think the 28 is correct?

    IF any of my assumptions are incorrect about the engine/charging system, please correct me. Bad info is worse than no info.

  • sswinehart
    11 years ago

    First check the battery voltage with the tractor off. If the battery is fully charged it will be 13+ VDC. If it is under that it is not being charged. Then start the tractor and advance the throttle about 1/2 way and check the voltage to see if it's charging. You should have about 14 volts. If not, the charging system is not working.

    There are only two things it can be - the stator as mentioned previously or the voltage regulator. I would bet on the voltage regulator as they go bad from heat and vibration while the stator has very little that can go wrong with it.

    Locate the voltage regulator, and use multimeter on the Ohm setting. Start at the top left pin and touch all of the other pins in the regulator connector. If you get resistance (Ohm) readings proceed to the next pin and repeat, etc. until you have checked all of the connections. If you find any that are open (infinite Ohm reading) you have a bad voltage regulator.

    If the voltage regulator checks out OK - then proceed to the stator and test that as previously described.

  • bill_kapaun
    11 years ago

    A normal, fully charged lead acid battery has about 12.6V, not 13+.

    IF things are charging, voltage at the battery terminals should be noticeably more.
    How much depends on the state of charge and the capacity of the charging system. With a badly discharged battery a lower capacity system will be "drug down" more than a higher capacity charging system.

    With a fully charged battery and minimal electrical load, THEN you battery voltage should show 13+, approaching 14V

  • krnuttle
    11 years ago

    While every thing said is valid, some times a battery will check OK, but because of age will not perform properly.

    How old is the battery? In my experience they must be replaced every 3 to 4 years.

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