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Tom_Barb's avatar
Tom_Barb
Explorer
Aug 26, 2016

Servicing the genny

Haven't used the AUX gen-set in nearly a year, so today I decide to change the oil and filters, not a big job by its self but when you find the entire bottom of the generator mount tray corroded, it becomes an all day job.
Oil and filter had 10 hours use total in 4 years, yeah I know I'm bad. but we are always in the camp grounds anymore.
The generator is out, tray is off. and in the morning it will be taken to the sand blasters to be stripped, then powder coated. then it all goes back in.
  • Trackrig wrote:
    n3eqf wrote:
    The usual enemy of a gas generator is fuel - leaving a generator set unused with fuel in the tank (and fuel line and carb) for a long time will likely spell trouble. Old gasoline gums up everything with what resembles varnish.


    The OP has a 7500 Onan Kabota 3 cylinder diesel.

    Bill

    Which by the way, diesels don't make the acids during the combustion cycle that the gas engines do. Thus the oil in a diesel only gets soft carbon particulate matter in the oil. this is why we can run longer on oil changes. Th oil I just dumped, looked as good as the day I put it in. filter same same. these little diesels simply don't have the corrosion problems the gas engines do.
  • n3eqf wrote:
    The usual enemy of a gas generator is fuel - leaving a generator set unused with fuel in the tank (and fuel line and carb) for a long time will likely spell trouble. Old gasoline gums up everything with what resembles varnish.


    The OP has a 7500 Onan Kabota 3 cylinder diesel.

    Bill
  • The usual enemy of a gas generator is fuel - leaving a generator set unused with fuel in the tank (and fuel line and carb) for a long time will likely spell trouble. Old gasoline gums up everything with what resembles varnish.
  • barmcd wrote:
    Onan recommends you run it two hours a month under load and I've always seen back up generators exercised regularly.
    And I know of several remote cabins in AK that only get started and run a week per year. no problems??
  • Our generator sat unattended for 9 years in storage then started right up. its the only system that we didn't have wake up problems with. When I removed the shroud the interior looked new. 17 years old 83.3 hours total run time. only problem, corrosion on the outside of the aluminum base mounting tray.

    I don't understand the 2.5 hour requirement from Onan.
  • Onan recommends you run it two hours a month under load and I've always seen back up generators exercised regularly.
  • If you believe in following manufacturer's recommendations, even partially, the generator needs to be run periodically under load. Onan suggests 2 hours per month under some load. We use our generator when we are staying overnight anywhere we aren't on short power (DW uses O2 concentrator at night) and to run the roof AC's while traveling if it is very hot. So, we depend on it and it gets a monthly exercise. IMHO, if you are only running it couple of hours per year, you are asking for problems.

    I am a firm believer that mechanical things will let you down when you most need them if you don't take care of them.
  • I'm certainly not one who believes the generator needs to be run every month. Mine is either stored in very cold weather where it makes no sense to try and start it, or it's stored a couple thousand miles away. But having said that, I think it should be run more than 2.5 hours a year to warm up the components, dry out moisture, blow out the dust, keep the gaskets from drying out so they don't leak, to not loose the fuel prime, keep the contacts in the starter working, etc. The moisture in the air can go back up the bare metal in the muffler rusting it out if isn't heated and dried out occasionally.

    Yes, my 7.5 Onan sits built into the front end of my DP where it's protected from rain and snow, but I wouldn't call it weather proof - or at least not moisture and dust proof.

    Bill
  • Trackrig wrote:
    When you're on your way to one of the RV parks, run the generator the with the A/C on.

    Bill


    Most of our camping is done in weather below 60 degrees.

    Why do we believe the generator needs to be run often?

    Our 7500 Onan is a Kabota 3 cylinder diesel, running a solid state brushless alternator. contained with in a weather proof container.
  • When you're on your way to one of the RV parks, run the generator the with the A/C on.

    Bill