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Ccoddou's avatar
Ccoddou
Explorer
Oct 21, 2013

Onan Gen Set 7500 Diesel

I was on my way back from a trip this weekend and i discovered that my Onan Gen Set 7500 will not start. I have a full charge on the battery and all breakers are good (solid on / solid off). Is there something I am missing. It is definitely something electrical because I get zero power. When I left for my trip, it was working. I never used it during the trip because of the cool temperatures. I turned it over when I reached my destination just to check and it worked fine. On my way back home, (at night) I tried to start it for lighting and....nothing. On another odd note, my fridge wouldn't even work on the LP gas setting. Is this because it requires voltage to switch it? Any help would be appreciated.

If it helps, I have a 96 Winnebago Vectra Grand Tour, Cummings Diesel, Allison Transmission and a Freightliner (Osh Kosh) Chassis.
Class A

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  • Big_Katuna's avatar
    Big_Katuna
    Explorer II
    Oct 21, 2013
    How cold is it outside? Diesel genset has glow plugs. You might have to hold the start switch for several minutes before it will crank.
    Fooled many a man.
  • prism's avatar
    prism
    Explorer
    Oct 21, 2013
    Ccoddou wrote:
    I was on my way back from a trip this weekend and i discovered that my Onan Gen Set 7500 will not start. I have a full charge on the battery and all breakers are good (solid on / solid off). Is there something I am missing. It is definitely something electrical because I get zero power. When I left for my trip, it was working. I never used it during the trip because of the cool temperatures. I turned it over when I reached my destination just to check and it worked fine. On my way back home, (at night) I tried to start it for lighting and....nothing. On another odd note, my fridge wouldn't even work on the LP gas setting. Is this because it requires voltage to switch it? Any help would be appreciated.

    If it helps, I have a 96 Winnebago Vectra Grand Tour, Cummings Diesel, Allison Transmission and a Freightliner (Osh Kosh) Chassis.

    As I posted earlier but it seems to have been lost.It sounds like you have inadvertantly shut off the 12V disconnect switch.This will account for no 12v lites,no fridge power and No gen battery power
    its usually in the stairwell area of th MH
  • JohnnyT's avatar
    JohnnyT
    Explorer II
    Oct 21, 2013
    It does sound as though you do not have 12DC in the coach... and yes your gas absorption refrigerator requires 12 DC. Can you verify that your its your house battery(s) that are fully charged are fully charged?
  • 2ndhom's avatar
    2ndhom
    Explorer
    Oct 21, 2013
    Are you getting any 12 volt in the coach? Is the propane tank full? Is the cook stove working? Not knowing if your fridge shows fault indicators? Do you know if the Gen runs off the chassis or house batts? Can you grt to the gen starting solenoid to beable to jump from in to out terminal ... indicating if your getting juice?
  • Trackrig's avatar
    Trackrig
    Explorer II
    Oct 21, 2013
    Did the refer also work when the trip started on LP and then quit during the trip like the generator. Yes the generator is diesel, but I'm wondering if the the 12V power to both of them quit during the same trip.

    Bill

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