I finally got the bucket float fixed on my EX450, I think. Yanmar America customer service sent the tractor to a different dealer than where it was purchased. The head mechanic there had worked for John Deere for many years, and said this was a common problem, and was caused by the wrong oil in the system. Said the oil in geared xmissions vs. hydrostatic had to be different. Said the geared needed Warren 303. Evidently the dealer who did the 50 hr service used the wrong type. He drained, flushed and refilled. Called me and said all was OK. Went to their shop and tried it, it was exactly the same as when they took it. So much for the wrong oil type. I made him show me the container he refilled from - plain old J.D. 303 from tsc. After 8 months of arguing and a tolal of 6 weeks of the tractor being in the shop (2-3wk periods), Yanmar America authorized them to change the control valve. Lo and behold it works. I haven't quite figured out the relationship between regenerate and the float, because once in a while it will still float until I power down on the control, but I think it has to do with regenerate - still working with it. The valve the the J.D. fix is installing is a one way restrictor. I think it would solve the problem, but it is certainly going to slow the bucket dump down. If the valve has regenerate built into it, the restrictor should not be necessary, and in my opinion is a "band aid" for a design problem. I don't know if the same people design and/or build the loaders for both J.D. & Yanmar, but i suspect they do, and very frankly, the loader is a piece of crap. At one point in time I was able to talk to and engineer from Prince about this problem, and he told me quite frankly "we sell them the valve, we don't design their system".
