I don't know much about those particular models because my dealer friend didn't sell them at his Yanmar dealership.
That was back about 1980 and Yanmar had already made made a variety of compact tractor models and sold them all over the world.
At that time when Yanmar was just getting started in the US - for the first time - late 1970s/early 1980s, the literature shows that several of the models could be had with either the 8/2 manual transmission or the power shuttle shift transmission.
On models that could be had with either transmission, the manual shift model designation had zero for the third number and the power shifts had six. The ones I remember from the advertising and parts books were the 180 vs 186, the 220 vs 226, and the 330 vs 336. There might have been others. I don't think that my dealer ever sold any of the manual shifts; they were only slightly less expensive than the powershift. As far as I remember everything else was the same.
But then as now, there were customers who wanted the simplest tractor possible, and a 4speed manual shift/manual clutch with hi/lo was exactly that. I think that time has proven the powershift to be as reliable or more so.
Sometime in the 1980s, John Deere made the deal to begin selling Yanmar compact tractors painted green as JD compact tractors. JD eventually required all the USA Yanmar dealers to close down as well. That led to a big warehouse sale one month in about 1989?? of new/old Yanmars from Yanmar's warehouses. I remember getting a phone call asking if I wanted a new YM336D for $9 or 10K. No warranty and fire sale prices. But add a loader to that and the Yanmars were STILL higher priced than lots of other compacts. Maybe some of the old manual shifts sold from the warehouses at that time.
For their compact tractor line, JD chose to ignore the powershift and reached back to the simpler, older Yanmars, changed the engine specs a little, left the rest pretty much the same, and went back to the manual shift. Those were less expensive for dealers to stock, and so became the JD 650, 750, 850 and 950.
I have no idea what parts are interchangeable. I wouldn't venture a guess. Well, except for engine parts. I believe the engines were identical.
Anyway, if you run across one it should be an excellent old tractor.
rScotty
