Attaching King Kutter 48BX to RK 21

[HankinOhio]

Today I hooked a King Kutter 48BX tiller to my RK21. I dont think this tractor was designed to handle a 3 point pto powered implement, at least not something that operates below the plane of the wheels, eg. a tiller 6" in the ground.
I jacked the tractor up so that when the 3 point was all the way down tiller tines was just above floor level (this is MAX BELOW ground position). This position required the longest shaft length. Next I raised 3 point as high as it would go ( MAX ABOVE ground position). This position required the shortest shaft length.
If you cut the shaft to accommodate the shortest distance (as you should), it WILL NOT be long enough to stay engaged when it is in the lowest position . I cut each section of shaft at 7 1/2 inches, measuring from the ring that locks the shield on each shaft. This left about 1/8 inch of travel between the shafts when 3 point is all the way up. I have what looked like about 2" of engagement on the shaft when the tiller tines were about 4" in the ground. There is not much room for error in sizing a tiller pto shaft on a RK 21. I also turned lower link mounting pins inward which seemed to make hitching it up easier
I will remark that when the tiller is all the way up it is plenty high enough for traveling. If there was a way to limit the upward travel of the 3 point the shaft could be cut a little longer. I chose to err on the short side so pto damage is avoided by too long a shaft and live with the possibility of shaft disengagement when tiller is deep in the ground. Its the lesser of 2 evils.
Hope this helps, we'll see how well it works this fall when I till the corn stubble in.

 

[LS Tractor Owner]

Sounds like you mis-cut the shaft......

The shortest point of the shaft is when it is horizontal to the tractor, give or take a little bit. Basically the "full up" and the "full down" lengths should be close to the same.

Granted, with a tiller, it won't drop as low as say a finish mower. You can adjust the lower 3 point arms by extending the links attaching the lower arms to the lift arms, making them longer. This will also stop lifting the attachment to high.

I don't have an RK tractor, actually never saw one, but 3 point hitches are almost basically the same. What you are describing is very strange.

Hope it works out for you.

 

[HankinOhio]

The attachment point for lower links is about 8" below the pto (this is the odd part) It really throws the whole geometry of the 3 point, pto pair off. The ball joints of the lower links are closest to the pto shaft when raised all the way up. Have used many tractors, own 4 with 3 point hitch at the moment, and have never seen this geometry, but this 21 is the smallest tractor I have ever owned. Never used a cat 0 but this must be a cat 0 with cat 1 pins.

 

[Yander]

Can you send a pic of the tiller and the tractor? Not sure why you jacked the tractor up. I have never heard of doing that for measuring and cutting a PTO shaft. I usually hook them up to 3pt. get the implement gear box shaft at the same level as the tractor PTO. Measure from the tip of one PTO shaft to the notch in the other shaft with the implement hooked up.

That will be the length minus about an inch and a half to two inches to allow some room for the shaft to slide a little as it needs to.

There are good Youtube videos out there.

 

[HankinOhio]

If pics are in correct order 1st is tiller all the way up 2nd sitting on the ground..3rd buried in ground while tilling...4th the reason I jacked the tractor up before I cut shaft. Tiller moves away from pto as it lowers. I needed to make sure shaft would be long enough when in working position. Take note of the distance from end of shaft attached to tractor and the white ring that is the shield bearing on the joint attached to tiller

 

[HankinOhio]

The red marks denote the end of inner shaft when tractor was jacked up and tiller dropped as low as it could go

 

[Yander]

I see what you mean. That is odd for the shortest length to be at up all the way. At least I don't think mine is that way.

 

[HankinOhio]

I have seen this before but not nearly to this extent. Thats why I felt compelled to post. If I had noticed this before I bought the tractor, I probably would have passed. I bought the tractor specifically for mowing the lawn and tilling garden. The range of motion going below ground level involved with a tiller makes the situation a lot worse than something that only lowers to ground level, as with a brush hog, or finish mower.