3 point hitch help needed for S470D Buck

[Botetourt]

My Buck doesn't have the original lower lift arms, I believe they're from Kubota. No issues in the last yr with a blade, but now I've got a Woods RDC54 finish mower. I have the lower hitches on the mower extended out. As Woods prescribes in their manual, I have the top link lined up with the lower hitch points, and the front wheels lift off the ground before the rears. My problem is when I lift it, it will contact the Buck's rear tires. I'm just using it in my own yard, and it seems to mow great, but I'd like to be able to lift it for transport and cleaning, etc. I'm not real good with the geometry of the 3 pt system- can this be adjusted better somehow, do I need longer lower lift arms, what? How long are the original lift arms?
Thanks

 

[284 International]

Try putting the top link into the lower hole on the tractor. That may angle the mower enough that it will clear.

 

[oliver28472]

I'm wondering if you can change the lift points on the mower for the lower arms so the offset is toward the center instead of the outside. Your front mower wheels probably come up first because of the built in float thingy on the mower that the top link hooks to. That has to have some play for uneven ground. Do you have the manual for that mower? I pulled on online and it mentioned different hitch positions:

RDC54 Only
The RDC54 has two mower hitch plate attachment
points (D). It may be necessary to change the mower hitch plate attachment point to obtain proper tire clearance and/or lift height.
Front Caster Wheel Interference Check
NOTICE
■ Do not operate tractor and mower until this
interference check has been performed. If you
change tractors, you must perform the check for
that mounting.

 

[Botetourt]

Yes, I have the manual and tried the hitch plate attachment both ways. The only difference is the lower hitch mounts extend out towards the tractor another couple inches. It seemed better, and makes sense to me, that the mounts sticking out further would help, but maybe not. There is no side-to-side adjustment of the hitch on the mower. I used a couple washers to keep the lower arms towards the center, the spread between them using the washers is 26 inches. The warning about the front wheels hitting the rear wheels of the tractor is what concerned me. The mower gets closer to the tractor when I lift it. No problem when on the ground, as long as the check chains are fairly tight.

I'm wondering if you can change the lift points on the mower for the lower arms so the offset is toward the center instead of the outside. Your front mower wheels probably come up first because of the built in float thingy on the mower that the top link hooks to. That has to have some play for uneven ground. Do you have the manual for that mower? I pulled on online and it mentioned different hitch positions:

RDC54 Only
The RDC54 has two mower hitch plate attachment
points (D). It may be necessary to change the mower hitch plate attachment point to obtain proper tire clearance and/or lift height.
Front Caster Wheel Interference Check
NOTICE
■ Do not operate tractor and mower until this
interference check has been performed. If you



change tractors, you must perform the check for
that mounting.

 

[Botetourt]

Try putting the top link into the lower hole on the tractor. That may angle the mower enough that it will clear.

I'll try that this weekend, although I don't understand why it might work. They told me at Valley Power last yr to generally use the upper top link mount, that the lower one was for tillers. But what do I know.

 

[284 International]

Using the lower hole will make the rear of the implement rise more. That will, hopefully, tilt the wheels back away from the tractor tires.

 

[skylarkguy]

It is kind if hard to tell in the pictures but it seems to me that your top link is fully extended. If you cranked this down, drawing the top of the mower toward the tractor then it would push the front wheels away from the tractor. The mower would no longer be parallel with the earth when raised but it would still work when on the ground.

 

[Botetourt]

It is kind if hard to tell in the pictures but it seems to me that your top link is fully extended. If you cranked this down, drawing the top of the mower toward the tractor then it would push the front wheels away from the tractor. The mower would no longer be parallel with the earth when raised but it would still work when on the ground.

I'll try that too. All of you seem to be working towards getting the rear of the mower lifting more than the front, which would seem to keep the front wheels of the mower off of the tractor tires, but Woods says for the mower to float properly, the front wheels should lift off the ground before the rear wheels when lifting the mower. Anyway, I'll try these and see.

 

[284 International]

All of you seem to be working towards getting the rear of the mower lifting more than the front... Woods says for the mower to float properly, the front wheels should lift off the ground before the rear wheels when lifting the mower./QUOTE]

The two are not mutually exclusive. The timing of front vs rear lifting first is a function of top link tension. As long as the top link isn't under tension and is hinged on the mower, the front will lift first. Using the lower hole will cause the rear to raise faster, but not affect the order of ends raising. You will also be able to shorten the top link, too, most likely. Hopefully the combination will gain enough clearance to make your combination operable as you desire it.

 

[oliver28472]

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.

 

[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