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Ldworak's avatar
Ldworak
Explorer
May 11, 2015

Onan 400 series generator battery

I just purchased my first RV. A 1999 Jayco Eagle. I believe I need a new battery as it won't start the generator. It does start with a large battery charger attached to it. There is enough juice for lights and low amp things, but when I try the generator I just get the clicking noise. I had it checked and the amperage is only at 250. My question is this. The battery is a marine battery with 625 cranking amps. The book only calls for a 350/450. Will it matter if I get the same replacement as what's in their now? FYI, There is also a Power converter/charger attached to the system that has been plugged in.
Thanks
Len
  • j-d's avatar
    j-d
    Explorer II
    May 11, 2015
    ^^^ Will hopefully await a positive reply. It'd be a fix that costs less than a battery, and replacing the battery won't help bad connections.
  • Ldworak's avatar
    Ldworak
    Explorer
    May 11, 2015
    After further review it looks like the braided ground wire has been fried at one point. ??? I will replace and go from there. THANKS
  • j-d's avatar
    j-d
    Explorer II
    May 11, 2015
    If this RV uses a "deep cycle" "house battery" replacing it is just fine. More capacity than the genset might call for doesn't hurt. Less and it won't crank, and gensets are quite demanding. Our house battery seemed fine till it wouldn't start the genset. Stopped at WalMart, got a Deep Cycle, installed in parking lot, all back to good.

    Just be sure all your connections are clean and tight, and that the battery's been charged, before going off after a new one.
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    May 11, 2015
    Amperage at only 250 is nothing I recognize as a result of any type of test.

    Use a handheld digital meter

    Stab the auxiliary battery posts not the clamps or cable with the meter probes.

    Have a 2nd person crank the generator. What voltage do you see?

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