Forum Discussion

bgitler's avatar
bgitler
Explorer
Apr 18, 2015

Generator not making a sound

I have an onnan 4000 generator. Yesterday I pulled my motorhome out of storage and everything started up great except for the generator. I pressed the start button and the light on the switch blinked 3 times, but it seems like it has always done this. There was no clicking sound like it would normally make when it is trying to start. I pressed the prime button but again there was no clicking sound and the light on the switch did not turn on.

Now whether I press the prime button or on button nothing happens. One time when I pressed the prime button it lit up briefly but then turned off again. It seems like the generator is not getting enough power from the coach battery, and possibly not getting any at all since now there are no sounds and the light on the switch does not turn on. However, the battery does have enough power to open the slideout so it isn't dead.

I also found the fuse rocker switch located on the side of the unit. I moved it to the opposite side and then back again but this did not appear to do anything.

Also, I've read about low oil being an issue and I did change the oil to rule that out so it shouldn't be a problem. I used about a quart and a half.

Thank you so much in advance, very frustrated right now!
  • bgitler's avatar
    bgitler
    Explorer
    Apr 20, 2015
    I wanted to post a follow-up. Saturday morning I checked the water level in the coach battery and it was full, also plates were in excellent condition. There was a little bit of corrosion on the cables and battery so I sanded it off. Next, I connected the cables to the battery again, but made sure they were securely fastened. Pressed prime on the generator for about 5 seconds, heard a click, pressed start, and it started right up!

    So, it looks like it was simply an issue of the cables either not being securely connected, the cables having a poor connection due to corrosion, or maybe a little of both. Either way, it's a beautiful thing when the fix is as easy as this one!

    Thanks everyone for your input!

    Ben
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Apr 18, 2015
    Sounds like Dead, or disconnectd batteries to me.. Generator NORMALLY runs off house battery (But may run off the other one) SLides also (Same but may).

    If instructions say to slide sides ONLY with engine running.. They hook to chassis.

    I have had my "Connect" Switch fail.. Also tripped breakers or blown fuses can simulate Disconnect,, In fact that is their job.
  • DrewE's avatar
    DrewE
    Explorer II
    Apr 18, 2015
    I would try starting the main vehicle engine before cranking the generator.

    It's possible your generator may be wired to start from the chassis battery rather than the house battery. Even if it does connect to the house battery, having the engine running will still let you get starting power from the chassis system via the battery isolator. If your problem is insufficient voltage/power, this should help solve that.
  • Golden_HVAC's avatar
    Golden_HVAC
    Explorer
    Apr 18, 2015
    I would take the coach someplace and fully charge the batteries from shore power before doing anything else. It might take 24 hours to fully charge the battery. Also check the water level in the batteries. If that is low, the battery might be bad (if you can see the plates that is really bad for the battery, and distilled water must be added before further charging or starting the engine again).

    Your on board charger should be in the 45 - 65 amp range and should put out about 30+ amps to the battery, fully charging it in about 2 days. But it should be full enough to start the generator in 24 hours.

    If it cranks and will not fire up, then starting the engine can help, because once the fuel system is pressurized, it will help 'push' gas into the generator.

    Good luck!

    Fred.
  • cjoseph's avatar
    cjoseph
    Explorer
    Apr 18, 2015
    From my 7000, owners manual, three blinks is a service level code.

    Press the stop button once more. You will get the code. It will be a 2-digit code. The light will blink X times and then XX more times.

    Check your owners manual for the codes for your Onan. I think they are pretty uniform from one model to another but can't be sure.
  • bgitler's avatar
    bgitler
    Explorer
    Apr 18, 2015
    I just took a quick look at my battery and did notice that I only have one negative wire attached to it. Would the generator be grounded to the underbody of the motorhome or would it run to the battery. I'm wondering if that could be the problem. It's too dark and late to get a very good look, I'll go back at it tomorrow.

    Thanks again!
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Apr 18, 2015
    Battery connects to slide out may be good BUT that doesn't mean battery connections to generator are.

    Check for 12V DC AT generator connection and that grounds are clean tight.

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