Update; 560 gas wont run under a load

He put new gas in ,better stuff and still no change... but he did notice the carb frosts up and gets cold and condensation starts to run off it ; also is there a heat exchanger or something like that above the carb that could be a part of this trouble ??

The main jet (or a passage is probably still to blame. The condensation is just very normal (it is why spray cans get cold at the nozzle) getting enough fuel is the issue. Jim

Yea ya have a butterfly up in the manifold that is suppose to open and close to warm the intake then open to let the heat away . Now in cool or high humidity the carb will sweat and even frost up if cold enough for a short time. . Did you check the timing at full throttle and what heat range plugs are in it . If your working it and this year i noticed when cutting hay with the 706 and a 1219 J D haybine that it was like trying to plow as it was taking a lot of power due to the extra heavy hay crop this year. So if ya jumped up to the 93 octane and the main fuel screw is five turns out the plug heat range is in the C-86 A C -D15Y champ or the 386 or 3116 Auto Lite and your fuel system is full flow and no pluged air filter then you may have done more damage and your in for a rebuild . That is about all i can tell ya setting here and not being there and checking myself .

I am thinking that the timing is not what it should be on it . As who knows what was done to the 560 over the years as a lot of them were upgraded to 706 spec. when rebuild time came , have ya ever met a farmer that said his tractor had enough power . All i ever got was CAN YA get me 15-20 more out of her.

If the problem does not start to occur until the carburetor starts to frost up, the problem may be ice forming around the nozzle tube blocking the flow of fuel. A working heat riser valve is necessary to overcome this problem.

Got to get in on this discssiion a little. As the 560 ignition timing is 30 degrees btdc and a 263 in a 706 is only 22 degrees at a higher rpm, maybe you should play with just retarding that high end of the timing down closer to 706 specs. Can't hurt a thing until you get so late it lacks power or heats. Have seen a few of those little six bangers fry , melt pistons over the years but around here no one really works them hard any more. I broke in mainly working on trucks and pickups with that basic engine, first thing I said when I saw the new 560 come off the truck was, what the h---, they put a darn BD engine in a tractor. Back then I wasn't privy to what was coming new as I was new also so it was kind of a shock. But, that being said , I just partially tore down a 560 diesel, pistons are shot, top rings can move up about a quarter inch due to erosion where injection takes place, has rod bearings marked '63. I know head had been off several times and assembled less than precise. Don't know about lower end. Five out of six pre-cups were turned 180 degrees, only one that was not was stuck in so apparently they didn't take it out. Haven't decided how far we are going on this one yet. Had head gasket blown between two cyls but even at that it started under own power. Couldn't believe it after I got it tore down somewhat.

It is a sure thing if the advance is toast!! Jim