D2 Pony Motor Runing Need Help

This might not be the problem but if the mag is not timed right sometimes just switching the plug wires from one hole to the other that they will be in time esp. if you timed the mag. marks to the camshaft gear through the pipe plug hole up behind the mag.so try it & see if it run better & if not then it has to be another problem.Are the plug wires any good so maybe they need new ones.

S J One Thing I Know Fore Sure Is The Mag Is Timed Right Checked It Several Times Even Tried To Advance It A Tooth Than It Would Not Run At All . It Almost Felt To Me Like The Timing Is Very Late .

To check timing, find "MAG" mark on pony flywheel, set this mark to match mark on block approximately @ 12 o'clock. Then thru plug hole upper back marks should line up on cam gear and magneto. Last, rotor should be directly on #1 cylinder (starting side) wire. If this is correct, then start up, adjust high idle fuel flow with adjuster screw on top of carb float body. This adjustment is BACKWARDS, in makes it richer ( I know, but thats what the book sez), adjust until smooth running at highest, and fatten (richen) up a hair. Final engine speed is done by the governor spring adjustment, tighten to 3350rpm, if you don't have a tach, match it to the sound of a Harley at 3300 rpm, lol!, or this rpm is just enough to "pop" the main block over when she's ready. Too low a pony rpm just won't turn the main over fast enough to catch. Too high an rpm and the poor pup will trip over itself and disintegrate. Sounds like the dry soot foul is telling you low idle may be too rich as well. Low idle is 850 rpm, adjust as necessary. Good luck, and keep us posted!

Take a look at the governor/throttle lever/throttle control rod. The governor has direct control over the throttle plate in the carburetor except that the throttle control can limit the governor arm travel and make the engine run slow. with the engine stopped, when you push the throttle control in, the governor should pull the throttle open.

What this means is that if the governor isn't responding, the engine won't speed up just because you push the throttle in. The back can be removed from the governor and the pivots inside oiled up if just oiling the output shaft pivot doesn't free it up. There is also a small plate on the pulley end that can be removed and a small amount of oil put inside to oil the bearings of the main shaft and the flyweight pivots etc which are located inside the pulley.

Sparkplugs are also a trouble spot with some swearing by different brands of plug and others swearing at them.😄 I believe Champion D16 and Autolite 386 are about the coolest range 18mm non-resister plugs that fit these engines. I have a D21 plug for the D6 that's been around here for a long time, so if you want something hotter, you can go up some.

Wires should be solid core WIRE for best results, but I know I have some resister wires that are working.

Remember, both the low speed mixture and the high speed mixture are backwards, IN to richen the mixture, OUT to lean it. I would start with the governor.

To check timing, find "MAG" mark on pony flywheel, set this mark to match mark on block approximately @ 12 o'clock. Then thru plug hole upper back marks should line up on cam gear and magneto. Last, rotor should be directly on #1 cylinder (starting side) wire. If this is correct, then start up, adjust high idle fuel flow with adjuster screw on top of carb float body. This adjustment is BACKWARDS, in makes it richer ( I know, but thats what the book sez), adjust until smooth running at highest, and fatten (richen) up a hair. Final engine speed is done by the governor spring adjustment, tighten to 3350rpm, if you don't have a tach, match it to the sound of a Harley at 3300 rpm, lol!, or this rpm is just enough to "pop" the main block over when she's ready. Too low a pony rpm just won't turn the main over fast enough to catch. Too high an rpm and the poor pup will trip over itself and disintegrate. Sounds like the dry soot foul is telling you low idle may be too rich as well. Low idle is 850 rpm, adjust as necessary. Good luck, and keep us posted!

My sugestion is go around the other side and work the linkage from the govorner both ways see if it speeds or slows I just got a D2 from a guy who could never start the main . It was becasue throtle linkage was on wrong side of the gov. linkage and would allow pomy to turn fast enough to start I walk around pushed the gov. link. and away she went now his pissed cause I wouldnt let him have it back. He paid the local dealer $3800 and sold to me a yr later for $500 and on another D4 the gov is sticky you have to move by hand also.

Everything that has been said is really good advise. I know for me I had that kind of problem one day taking my tractor to "Herb's play day". What had happened was that everything worked fine, I loaded the tractor on my trailer
and got up to my destination. During the traveling one of the spark plugs came off at the cap. So when I tried to start it it would either not start or if it did start, it barly ran. I couldn't make the engine go any faster, and I certainly didn't have enough power from the pony to start the big engine. When I looked things over and found the problem, the pony of course took right off.
You might try looking at the spark plugs and wires. Check to see if your getting fire on both plugs.
Good luck 😊
Mike

The most common problem with these ponys is not getting enough gas. The tank is so close to the carb that there is little pressure. I tore one completely apart because it would only run on one cylinder. I found nothing wrong with it. After I put it together I took the top off the carb and blew out the jets and it runs like a champ.

The float stuck on the 212 pony yesterday and the farm crew got it started once by installing new plugs (Ford 6 cyl???). Then I came along and thought I would do a quick pass up and down the driveway. The pony oil looked dilute and it was too full,😕 so I changed it thinking someone forgot to shut off the fuel.

No luck starting at all, then I find out what they went through starting it and the diluted oil began to make more sense. So we pulled the hood off and cleaned the carburetor out.

I had cleaned it some about a year ago when I had the engine out chasing oil pressure troubles, but I never got it to run right, it always had to have a lot of choke to run. Yesterday, I was able to get both the idle jet and the main jet out and clean them and the passageways in the bowl. there's also one under a plug in the bottom corner of the bowl that has a tiny hole in it that could be clogged. Get the exact size screwdrivers if you want to take these out. Even then, I wasn't able to get them out last time when the grader had been sitting for several years.

It runs a lot better now. Still has trouble accellerating from idle without dropping to only one cylinder. I think it needs the correct plugs and we'll be fixed.