Forum Discussion

HadEnough's avatar
HadEnough
Explorer
Jul 04, 2018

Happy 4th of July From my Onan 2500 LP :(

Today, mid heat wave, I was dry camping as usual and lost the Onan 2500 LP generator.

It had been running roughly, so I ordered the air filter which cleared that problem up 100% a few months back. The air filter arrives tomorrow.

Today, however, the thing was running roughly at idle, then ok with a few skips here and there under air conditioning load.

Randomly, it stopped just like it would when you run out of propane.

Checked that it had propane and tried to restart. Not even a hope or prayer of it catching. Just turns over and over.

Also, there is a fair amount of oil that's been sucked up near the carburetor I assume due to the dirty air filter. It's certainly done this before.

Hypothesis is that the air filter is just plugged and has oil on it and isn't letting enough air in.

Anyone have any other thoughts?
  • pnichols's avatar
    pnichols
    Explorer II
    Jul 06, 2018
    FWIW, I've had the same E3 spark plug in my 4K gas Onan for years. It has always started right up and runs with a smoother, less burdened sound than it did with Champion plugs.

    As a side note, our Onan has a convenient knob right behind it's side door with a graduated scale on it for adjusting it's air/fuel mixture to match the altitude that you're camping at. I've never read in these forums of anyone paying attention to this adjustment on their built-in Onan generators.
  • HadEnough's avatar
    HadEnough
    Explorer
    Jul 05, 2018
    wa8yxm wrote:
    I have an ammo case. It has spare oil filter, Spare fuel filter, Spair air filter, Spare spark plugs.. And the needed wrench for Oil and plug.


    Nice!

    I have no oil filter on this little Onan and it's propane so no fuel filter, but do have the tools to change the oil and plug as well as a spare air filter now. Gotta get that spare plug too. Having a kit like yours makes a lot of sense.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Jul 05, 2018
    I have an ammo case. It has spare oil filter, Spare fuel filter, Spair air filter, Spare spark plugs.. And the needed wrench for Oil and plug.
  • HadEnough's avatar
    HadEnough
    Explorer
    Jul 05, 2018
    Well, we were right! Solved!

    New air filter and it runs like a champ.

    Watch those air filters. The moment you see misfiring or any oil seeping around by the intake, change it!

    Lots of headaches avoided this way.
  • HadEnough's avatar
    HadEnough
    Explorer
    Jul 04, 2018
    MEXICOWANDERER wrote:
    When gasoline will light off, LPG won't. So my 2 cents is it's X2 saturated paper blocking the air.


    Thanks. That's where my thinking is as well.
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Jul 04, 2018
    When gasoline will light off, LPG won't. So my 2 cents is it's X2 saturated paper blocking the air.

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