Replacement Carburettor High Altitude Main Jet
Generator Guru Says:
You will require a high altitude jet to run your unit 5000 feet/1524 meters or more above sea level due to the thin air changing the fuel-air mixture at these altitudes.
If your carb is having problems, this is a part that can very easily become clogged and can be the cause of many carburation problems, due to the careful sizing of the jet allowing the correct fuel flow for your unit. Even the smallest particle of dirt can disrupt this, so even if this looks clean, it may still be the problem.