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Colo_Native's avatar
Colo_Native
Explorer
Mar 12, 2018

GENRATOR High altitude Jet

I have my Champion generator and did the break in, now I put the high altitude(3500'or higher) and I must say it was a PITA how many people leave it in or don't use it because it is a PITA. I would say about half the time I would be at altitude so Is it really needed?

28 Replies

  • Chum lee wrote:
    Running your generator at higher altitudes with the sea level jetting will cause it to run rich. It may smoke a little, maybe not. It will use more fuel than necessary and it may foul the spark plug and/or dilute the engine oil with fuel. Running it at sea level with the high altitude jet will cause it to run lean. You may experience loss of power, hard starting/rough running, or excessive engine temps.

    Time will tell how it effects longevity. Your choice.

    Chum lee


    I always thought it was just the opposite. Higher the altitude, thinner the air, fatter the jet orfice to compensate foe the thinner air.
  • another problem with a small jet at sea level you can burn a hole in the top of the piston if you run it too lean for a long time
  • Overhead camshaft, direct port fuel injection with an ECU.

    Carburetors are sooooooooooooo...

    ...YESTERDAY

    (valley speak)
  • I have a champion generator and did call to get the jet. But in discussions with the tech he stated that it just would make it run a little smoother at elevation but it will not produce any more power. We are usually at 9000' and I did not swap the jets. It runs good as is so I have the jet shoved in a drawer somewhere. What elevation are you staying at?
  • Chum lee wrote:
    Running your generator at higher altitudes with the sea level jetting will cause it to run rich.


    It's unfortunate manufacturers don't offer gensets with fuel injection ... won't overcome the effect of power loss at altitude but would eliminate the need to fool with carb jetting. Honda's EU7000is is one that comes to mind that does have FI, unfortunate they chose to not offer their new EU2200i with FI as that certainly would have been an attractive feature over the competition.
  • Running your generator at higher altitudes with the sea level jetting will cause it to run rich. It may smoke a little, maybe not. It will use more fuel than necessary and it may foul the spark plug and/or dilute the engine oil with fuel. Running it at sea level with the high altitude jet will cause it to run lean. You may experience loss of power, hard starting/rough running, or excessive engine temps.

    Time will tell how it effects longevity. Your choice.

    Chum lee
  • Altitude +1 ft above sea level or 12,000 ft above sea level. The devil is in the details...

    I drove a race-car with a 400 HP engine on the street 50 years ago. I rejetted the Webers for 7,000 feet and did not notice snot for difference with -5 sizes reduction in power jets in all 4 carburetors. It was a Sunbeam Tiger.
  • Colo Native wrote:
    I have my Champion generator and did the break in, now I put the high altitude(3500'or higher) and I must say it was a PITA how many people leave it in or don't use it because it is a PITA. I would say about half the time I would be at altitude so Is it really needed?


    Run it and find out?

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