Shafts 28 and 33 might be rusted and thus frozen. It was heck, but I was able to take it apart, clean and regrease. I had to make a special tool to get the shafts driven out. I consider myself to be about an 8 or so out of 10 on the level of mechanic. This job was not easy, but was pretty straight forward if you have reasonable mechanic skills.
My 4310 had symptoms of the 3 point not acting correctly to the lever's location.
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