kgrant, Wow! I had no idea you are in Alaska. That's really hard on freezing COLD Gasoline/Diesel engines on startup. If you are at an elevation over 1,000 feet, that will also cause the genny to run richer, carboning up the spark arrestor screens before their time. I am at 1,170 feet and had to "modify" the main jet so my new EF2000iS would not stumble when a load was applied. The stumble sounded like a lean stumble but the heavy hydrocarbon odor said otherwise. I easily diagnosed the stumble as being too rich by turning the gas off, then repeatedly cycling the Eco-Idle switch on/off/on. Guess what. The stumble went away after a few Eco switch cycles! It responded and ran better AS the carb bowl was running out of gas. Removed the mainjet, used a small hammer and a tiny steel pin and 1 light tap to reduce the indicated 67.5 opening by a microscopic amount. My multi size jet cleaning wire tool kit confirmed a slight reduction in size and so did the way the cold and hot engine responded to heavy load applications. I would have gotten a smaller main jet, but none is listed in the parts listing. Not even high altitude alternatives, unless I'm required to jump thru hoops to find one. No matter, with cautious restraint and past experience with similar power equipment mods, I got it right the first try. Soon confirmed by the cold engine's immediate response to a 1600W load -and- the hot engine's lack of it's former over-rich stumble doing the same. A big plus is the mainjet is screwdriver removable after easily removing just the 1 bolt retaining the carb floatbowl. Sweet.
As you must know, the owner's manual warns against putting covers or boxes around/over the running genny BUT they are referring to improvised rain or sun shelters, NOT a shelter from zero degrees F and much lower temps! It's not like it can or will overheat in those temps. Running it without the spark arrestor screens, although noticeably louder overnight, looks like it could be the long term plan. Otherwise you'll be forced to do a 2 or 3 day run between spark arrestor screen cleanings.
Using SeaFoam is the best "no wrenching" way to slowly decarbonize the combustion chamber (CC) and clean the carb internals. Too much has to come apart on the EF1000iS to decarbonize the CC because there isn't a removable cylinderhead like the EF2000iS and most all other generators have. That makes it cheaper to manufacture, but the engine has to be taken completely apart to manually decarbonize the head or do valve repair/replacement. I recommend an 80% of full sized low dose over many days rather than a stronger mix so the carbon is slowly recombined and dissolved away rather than loosened up and blown out the exhaust. Blow-outs can cause cylinder wall scratches if those extremely hard Carbon particles fall into that region.
BTW, was the "crank seal blowout" an actual seal blown out of position or was it just leaking badly?
2009 EF1000iS, 2011 EF2000iS, 1987 Honda EM-3500. (ready for anything!)