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zoostory's avatar
zoostory
Explorer
Nov 17, 2018

Brand New Onan QG 5500 not turning

Hey guys and gals,

Total RV newbie here. Living fulltime in a Thor Windsport 34R my wife and I purchased about 6mo ago.

I just tried to run our generator, just to break it in a bit, and it wouldn't turn over. I popped it open and primed the fuel, still nothing.

I then got worried cause we were still connected to shoreline power, so I unplugged the shorline, and now the lights wont even come on on the generator switch and the on switch does nothing???

I'm struggling to figure out what this could be? My wife said it worked when we first got the RV. I was out of town, and we had it in storage for a few months, if that means anything?

Our tank is just about 1/4 full.

Any thoughts are much appreciated!
  • Sounds like its the low fuel tank.
    Does anyone know if the genny will prime even with low fuel on that type of setup?

    Because hitting the prime button and listening for noise would help us know if his genny is getting 12v.
  • zoostory wrote:
    Hmmm... these are brand new batteries that we installed recently. How can I check to see if they are dead or not? Also, when I unplug the shoreline, I still have power to my wired lights, doesn't that mean the batteries are not dead?

    Make sure the battery terminals are clean and tight. A little corrosion can cause problems.
  • Happytraveler wrote:
    Our Onan Generator in our motorhome will not work when the gas tank is 1/4 full. I guess it's a safety thing.


    I believe the OP states the Onan will NOT attempt to start/turn over. That means he probably has a battery/12volt voltage problem. He needs to state if he tried to start the CHASSIS engine. His Onan may start from the Chassis and it is dead from 6 months of being parked.
    Fuel at 1/4 is not a safety thing. It is to keep you from draining the Gas tank when on Genset and then having NO gas to start and drive the RV. ALL correctly installed gensets in a Motorhome have the 1/4 tank pick up system. Doug
  • MrWizard wrote:
    start by checking the batteries
    the fluid level in the cells and the cleanness of cables and connections
    remove clean and tighten cables
    add distilled water if needed to the batteries

    use a volt meter and check battery voltage
    you may have a blown fuse between converter and batteries
    or perhaps the battery dis-connect switch is in the battery off position so the converter could not charge them
    your converter is working from shore power, because you have lights etc.. when plugged in


    I have lights when unplugged, too.

    Update: I just looked at the meter for both Batteries, they are both full and at 13.7v, so they're currently charging. They are brand new and should be healthy, like, 2 months old
  • start by checking the batteries
    the fluid level in the cells and the cleanness of cables and connections
    remove clean and tighten cables
    add distilled water if needed to the batteries

    use a volt meter and check battery voltage
    you may have a blown fuse between converter and batteries
    or perhaps the battery dis-connect switch is in the battery off position so the converter could not charge them
    your converter is working from shore power, because you have lights etc.. when plugged in
  • 2oldman wrote:
    Dead batteries.


    Hmmm... these are brand new batteries that we installed recently. How can I check to see if they are dead or not? Also, when I unplug the shoreline, I still have power to my wired lights, doesn't that mean the batteries are not dead?
  • Our Onan Generator in our motorhome will not work when the gas tank is 1/4 full. I guess it's a safety thing.

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