284 Injectior Pump/Govenor

It does sound as though either the fly weights or the rack is sticking.  The lubricant for the IP should be either motor oil or a non-detergent oil of comparable weight, according to what I've read.  I've also red that these pumps/governor assemblies aren't really user serviceable, other than changing the oil regularly.   There may be some fudge room in that, but I wouldn't know where to start – Bob Rooks would be the guy to know, probably. 

Based on things others have reported, you may well need to go to greater lengths to clean the whole fuel system if you actually do have diesel bugs.  From the fuel tank to the injectors themselves, everything needs to be cleaned scrupulously and completely purged of old fuel and then treated with a biocide.  That may wel mean disassembling the tank so you can boil it out, clean/replace the in-tank filter screen, clean/replace the screen in the sediment bowl, replace the inline filter, etc, etc.  Those bugs are pernicious little bastards and really hard to eradicate completely.  They can also corrode metal parts, resulting in the sort of sticking you think you're experiencing.

If it were mine, I'd start by flushing the whole system out with some solvent that won't destroy any seals in it – diesel fuel or, preferably,  #1 white kerosene.  Do that a couple of times and crank the engine with the compression release pulled to take the load off the starter somewhat.  Then refill with the proper amount of oil.  Some pumps have a dipstick and others just have a fill hole (usually the breather cap) and a witness hole where the oil pees out when its full.  Some pumps have one drain plug on the bottom of the governor housing and others have that and another one on the bottom of the IP housing itself.  If you don't have the manual for your engine you should get one so you know what you're dealing with.  Affordable Tractor Sales should be able to fix you up with the manual and any parts you might need.

I definitely would not recommend taking anything apart on that assembly without guidance from someone like Tommy at Affordable or Bob Rooks.  Those guys actually know something and I'm just repeating things I think I've read.

Jules,

You aren't going to get rid of any bugs by just adding a treatment, you have to physically clean as many fuel system components as you can. Any bugs that you see plugging fuel system components are already dead anyway – that's the black/brown sludge, billions of dead micro-organisms.

Rich is correct on the flushing media.