Honda EM2500 generator

Forest#2

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When it started smoking was the smoke blue or black, like black soot.

The reason I ask is oil smoke is blue, running rich will be black soot.

Was the engine running smooth?
Does that unit have the auto idle, where it will idle if a load is not placed on the unit and a switch set to AUTO?

If it's blue smoke just let it run. The crankcase was overfull with contaminated gas before and it has caused wet carbon/oil in the muffler and on top of the piston. It should clear itself after about maybe 30 min's. (engine and muffler has to get hot)

If it's black soot, shut it down, your needle/seat is leaking or the choke is stuck on, and the engine should be running rough if it's getting too much gas through the carb.
When you kill the engine turn off the petcock immediately or turn off the petcock and let it run out of carb gas.
 

larrypac

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Well, I had put exactly the specified amount of oil in but it was reading a bit high on the dipstick, so i drained out an ounce or two and smoke is gone. Thanks to all who offered advice and especially to Forest #2 who diagnosed the gas in crankcase.
 

slomo

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Could the piston/rings/cylinder have gotten damaged in that short of a time?
Sure, if you live by the ocean or maybe store this unit outside. Big temperature swings daily? I would pull the plug and fog the cylinders with Stabil's fogging oil. Standby generators sit for untold days.

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slomo

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Most likely the engine is burning off the oil/fuel in the sump.
 

Forest#2

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Not exercising gasoline operated standby by emergency generators every once in awhile is usually what makes them not ready to go when needed. Ethanol fuel is a no-no also

Before storing I usually do the following procedure so as to prevent/reduce possibility of a metal gas tank rusting and to keep the carb from drying out and making gunk. Turn the petcock off at the bottom of the gas tank and run the engine until it runs out of fuel, remove the gas hose from the carb or petcock and drain gas down to approx 1 gallon, then dump in 1/4 quart of ATF oil, enough to color the gas red, re-connect the gas lines and remove the carb bowl drain plug and let the ATF mixed gas go to the carb and when ATF starts flowing out the bowl drain re-install the drain plug and let the carb bowl fill.. Remove the spark plug and add spoonful of ATF slow crank the gen and then re-install spark plug and leave plug wire off. (or use the fogging oil mentioned above)
I do the same procedure also for plastic gas tank gen's.
When the gen is needed or to test later just add gas, usually 4 gallon to the existing in the tank, crank it up and let it smoke for awhile. It will run ok with the ATF/gas mix, just little bit of smoke at first.
Diesel, propane and Natural gas gen's are normally more reliable when coming out of standby storage.

Some of them older model Honda gens used a metal gas tank and if not taken care of will rust severely.
Also it's recommended to remove the electrical load from the older model Honda gen's BEFORE killing the engine so as to reduce chance of ruining the very expensive AVR. (Automatic Voltage Regulator) The reason why such is recommended is the Electronic voltage regulator tries to compensate for the drooping voltage/current of the load as the engine is dying.

Some of the AVR's for Honda emergency gens is in the $300 starting area. (and no warranty for electronics when purchased from a Honda dealer)
 
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bertsmobile1

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If you have oiled up the muffler then it can take quite some time for it to burn it off .
 
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