MY YAMAHA 6600DE GENERATOR STARTS AND DIES

The OHV engine requires periodic valve adjustment.

go on the net and search the make of generator Therre will be a page of specifications that will have all that information probably in pdf format.

This generator is equipped with an auto choke. What is likely occurring is as the engine warms up the choke is returning to the normal choke off run position leaning the mixture two lean to maintain operation of the motor.

This is occurring because the residual fuel that was left in the carburetor has evaporated and the gum residue is reducing the fuel flow through the carburetor. When the choke is applied the mixture is rich enough to support running and as the choke returns on its own to the run position the mixture leans out and the generator stalls..

Override the choke when the engine is starting to falter to confirm the problem. Continuing to attempt to run the engine possibly adding a carburetor cleaner additive to the gas will likely return the unit to normal operation.

If attempting to enrich the mixture by applying choke when the engine begins to falter does not work then a fuel flow problem to the carburetor may be the root cause. I would look for a plugged fuel filter or restricted fuel flow from the tank to the carburetor. What is happening is when the unit is at rest the carburetor is filling with gas and as it is running because of a restricted fuel flow the level lowers in the carburetor bowl resulting in a mixture to lean to run.

have checked the plugs

this sure sounds as if the low oil cutoff is activating for some reason , look at switch carefully to see any physical dammage (ck oil level as well)

time to remove the carb and clean it...

Not very much information in your problem troy but you might be drawing more amps than your producing. I had bought a nice little Craftsman electric tire pump but my Yamaha kept dying. After reading the labels, my 2400IS puts out 15 amps and my tire pump needed 18 amps, my friend now has a nice tire pump for his home use. I've seen post that RVers have to add the "booster" kit to start their air conditioners, extra power is needed to start them after that the 2400 can run them. Just a thought, try reading the metal tag on what your trying to run and see how many amps it needs. Anything over 15 will shut you down and some will need that extra "boost" to get them started. I seem to think I read somewhere that it is about $75.00 for the Yamaha booster kit.

You have a fuel issue and is most likely a blockage in the carb.

When you pull the bowl off of your carb is it clean? If not you have some contamination possibly inside. You might want to remove the carb and blow compressed air through all the vents a ports.

turn the throtle knob to while checking voltage & hertz