3 point hitch help needed for S470D Buck

[Botetourt]

Thanks for all the suggestions. I had a little time yesterday, and got it straightened out. Moving the top link attachment point to the lower hole on the tractor made all the difference in the world. I can't quite understand why, but it works. Also, I was then able to shorten the top link some, which helped a little more. Finally, I bolted on 2 $4 hitch pins, pointing towards the center, onto the lower hitch pin mounts of the mower. This moved the lower arms in a little bit, which moved them away from the tractor tires a little. Now I can lift the mower about 14 inches at the front wheels, about 17 at the rear wheels, without the lower arms or the mower front wheels contacting the tractor rear wheels. The front still lifts first, and the upper hitch is still has slack in it, and is roughly over the lower hitch points, all as Woods suggests. Didn't mow any, but pulled it around the yard, including some dips and rough spots, and it seems to track very well. I'm going to search for an explanation of what adjusting the various 3 pt components accomplishes, so I don't have to randomly try various things to see what works. The one thing I didnn't try after this was moving the lower hitch points on the mower back towards the mower deck (there's two choices, 3 inches or so apart). I really don't see how that would improve on the current set up. Also noted the difference the 400+ lbs of weight hanging in the air behind the tractor makes, when driving across the yard. I've got 150 lbs or so on the front, and the front of the tractor didn't lift up, but it is a noticeable difference. Thanks again, everyone.

 

[284 International]

I'm glad you got it functional.

The basic idea of "why it works" is centered on the geometry of the links. If the top link and your lift arms are the same length, and fastened the same distance apart in height, the implement will lift exactly level. Shortening the top link relative to the lower links will move the far end of the implement higher than the near end, even if it starts out level. The same thing can be accomplished by decreasing the separation on the tractor side. You're coming closer to a triangle in layout, which would simply pivot around a single point.

The multi-link design has some attractive benefits. First, it lets the tractor lift more than it otherwise could. The less separation between the links on the tractor side, or the shorter the top link, the less load the machine can lift, but it will lift it higher. Put another way, a short top link/reduced separation has less mechanical advantage, thus more movement, at the implement.

By adding the inward facing pins, you in effect lengthened the lower links (decreasing the effective top link length) and moved the mower farther away from the tires, too. Then, lowering the top link made the rear lift more than it otherwise would, and so did shortening the top link. These things can all happen and still have the mower sit flat, but you will notice the angle changes much more drastically when you lift the implement, compared to how it was before.

When I run my disk or am trying to finish grade something, I like to have the implement set such that it lifts as level as possible front to back, so that I can adjust the height or depth without so much impact on the angle of the implement. Conversely, trying to bash down heavy undergrowth with my brush mower, or to take big bites of a dirt pile with the box blade, I set the top link to the lowest pin hole, and shorten the top link if possible. This lets the back of the implement lift as high as possible.

It is good to do research and get your mind around what it will/won't do, or what adjustments are possible, but really the best way is to just go experiment. What works for my machine and implement combinations in my conditions may not give you anything like the results you are looking for. The basic fundamentals are the same, but the desired outcome is not necessarily identical.

 

[evan price]

You could also try going "old style" and remove the front wheels if you have chains from the lift points on the mower to the top link on the tractor. That is how the older mowers are set up.

My RM48 is like this, and it works great.

 

[slvrpkr]

i believe the Kubota lift arms are a couple of inches shorter than the Bucks as their rear tires are quite a bit smaller. i found that out as i was looking for new arms last week. i ended up having a shop weld new on ball joints. boy was that cheap. if you are stuck with the Kubota arms i suggest you find a machine shop that can add some length. that should solve the problem.

JG