Cleaned WD gas tank; runs better now but not great.

So update on my WD, since it's been awhile. Pulled the carb and the gas tank. Cleaned everything (spent like a week swishing nuts and bolts in the gas tank, and definitely got two solid handfuls of rust out of it). Been back together for a week and the sediment bowl is amazingly clear still. Very pleased with that.

However, the tractor itself still isn't running quite right. It fires right up when you pull the starter, and it idles great, but after it runs for about 3 minutes it starts to develop a "pop" or flutter (not like a miss, but... sometimes it's just a single pop, sometimes it's a double pop)... And when you open up the throttle, sometimes it seems like it becomes a bit choppy. Take it out and drive it around and when you get on a hill, it sounds like it's going to die. But open the choke up, and that doesn't help any.

I tried dinking with the carb, but just wound up opening it up enough so it blew black smoke at about 1/2 throttle, so that didn't work well. I've got it set at about 1 1/2 turns out for idle screw, and maybe a shade past 2 turns out for the main jet right now. Really confused on what to look at next. It seems like the engine just speeds up and slows down when the throttle is anything past idle (usually about 1/4 throttle) and doesn't run smoothly past idle or once she warms up.

Play with the timing. Try advancing just a bit first.

Check the point gap , too small of a gap lets it
idle but no power. Also slop in the dist shaft, if
it's noticeable , it needs a new bushing ....

Have you looked at your intake manifold gaskets? I have had to mill down the manifold on every tractor I have had. The gaskets on a WD don't seem to hold up all that well, and the exhaust ports tend to gas cut around the leaky gaskets. I have seen a lot of them that were not properly cleaned off of the intake ports, with a new gasket installed it can create a vacuum leak. Test for it with a squirt can of oil around the intake ports and see if it settles down. (I usually use a squirt can with gas in it) I also have found, just this year, a hard shell bug stuck in the internal passages of the sediment bowl, above the shut off screw, that was severely impeding the flow of gas. Take off the fuel line at the carb and verify a steady stream of gas. HTH

Will I hope you get the bugs out of it and bring it to Jacksonville in a couple weeks.

60 acre hillside - I assume this is pretty easy to do? What would have made the timing go bad, since it was running decently last year?

Dalex - Slop when you turn it forward and backwards, or side to side? Point gap is checked when it is at its maximum open, correct?

Little Ed - Replaced the manifold gaskets about 6 or 7 years ago. Seem to be in good shape still, but always possible. Just cleaned out the whole gas valve/sediment bowl when I had the tank off, and am getting good gas flow to carb.

centralilbaler - I was hoping to have her running good for the steam show, but the odds seem to be stacked against me. But I'll still be there; hope to see some of you folks again!

Took a picture inside the distributor cap.

Pic may be distorted, but should there not be 4 perfect lobes on that shaft? It looks like one good lobe and a couple of wore out lobes.. but... hey it could be the picture. make sure the shaft is tight and does not have play in it from a worn upper bearing. and make sure the points are cleaned and gapped correctly.