From what you say I wouldn't think rich, rich will keep running but feel "Boggy" like it didn't do much to give it more thorottle but it didn't cut out. You don't mention if it does this cold or ever has backfiring through the carb<indicates lean or burnt intake valve>
Let me give you a rundown on rich lean detection...
Your sparkplugs are readable and they will tell you lots and lots of things, given you are using the proper heat range to begin with.
If you suspect you are overly rich or lean you should remove your plugs and take a look at the insulator color. If it is black and sooty you have too large jets in the carb, too high a fuel level in the carb, choke sticking, or severly clogged air cleaner.. all of these will cause more fuel to flow from the carb..
On the other hand if they are near white<indicating lean> or very light tan color you may have trash in the jets and not getting the prescribed ammount of fuel per volume of air the engine is pulling. Could also have a fuel restriction in the filter or line also... I guess you know about the drain hole on the bottom of the fuel tank, mine used to get clogged with rust when I first started driving my scout again.
The appropriate color of plug insulators are tannish in color not approaching black nor white. Red indicates a probable octane booster and makes plugs impossible to read until you get some new ones unless you are sooty rich. Remember these are the only things inside your combustion area you can remove and look at.
They can tell you lots of things. If you have some right and some more light they can tell of more serious things like with split manifolds that feed off different carb barrels one jet may be clogged and another free giving a light color on the ones feeding from the clogged barrel...
On the other hand if the two middle ones are white and the two outers darker and you are loosing a little coolant you may have a head gasket leaking and the coolant washing the plugs white.
Last but not least if you have a non clear filter, cut it open and see what it looks like inside, rust can also get past the filter if very fine and get under the rubber on the needle seat and prevent it from closing allowing the fuel level in the bowl to raise and therefore run rich, some electric fuel pumps have too high pressure to begin with and will push the needle off seat anyways, a simple pressure regulator set to about 3 1/2 pounds will correct this if you find nothing else wrong.
Another thing is if the venturi size is too large for the ammount of air your engine is flowing, there will be no velocity of the air through the center which by the way is how a carb regulates how much fuel to give...but being a 345 I don't think that would be the problem. Have you had this prob ever since you got this carb?
I need somemore info but I'll help ya get it straight [img]images/graemlins/blush.gif[/img])
Just noticed it was a scout II, may not have the drain on the tank bottom, check the filter...
Look here also