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Onan 2.8KV hunts after thorough carb cleaning and tune up Tony 10-26-15  
I have an Onan genset 2.8 model 2.8KV FA26100B.

The gen keeps hunting when no load is on it. When 50% load is on it, it hunts less. When 100% (or close to 100%) load on it, it hunts very little but begins to degrade (hunts more) as minutes pass running.

I have done the following:

1. removed carburetor and left it soaking submerged in techron fuel injector cleaner for 2 days, then seafoam cleaner for 1 more day, then used a huge can of carburetor cleaner through all the orifices and jets I could see.
There was quite a bit of varnished removed as evident in the color of the cleaners...

2. installed a new air filter, fuel filter, and spark plug, all bought oem from Onan

3. using fresh fuel from the gas pump

4. carb main mix is at 1 3/4 out, idle mix is at 1 1/2 out.

After this tune up, it hunts less but still hunts, specially with no load.
Hertz show at around 62.5 +/- 2-3Hz with no load as it hunts quite a bit up and down on the RPMs, and hovers at around 59 with load, but it hunts somewhat still and as things are turned on or off and the load varies, so does the hunting.

What else can I do besides replace the entire carb?

Re: Onan 2.8KV hunts after thorough carb cleaning and tune up Tony 10-26-15  
Additional things done today after watching some videos and reading more:

removed bowl from carb, removed main and idle needles and cleaned everything up really well with qtips and more seafoam. also did the the bowl orifices and also up the center stack where the fuel is sucked from (attached to carb)
there was still varnish on it so I can only assume there is varnish in the places that I cannot mechanically get to with a q-tip.

the hunting is a lot better now but still some hunting as follows:

idle: up/down hunting: 62 hertz +/- 1 hertz
40% (+1000 watt heater): a tiny amount of hunting, 60.5 hertz +/- 0.5
90% (+1500 watt heater): no hunting, but it sounds pushed, like a truck going up hill and barely having enough power.... 60 hertz steady.
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