Draft control pinned out M7040

[fast*st]

So going over the owners and service manual the other day, silly thing, the draft control lever is inoperable. It moves but serves no purpose, so dig into the problem.

The book pictures show the top link pin holder and show it with two 12mm pins that go down through the shaft in the top link bracket. The top link bracket has a linkage that heads up to join up with the 3pt hitch height sensor. Well this bracket needs to move, but one pin attaches the sideways shaft to the gearcase, the second pin attaches the top link bracket to the shaft. We carefully unfolded the cotter pin and removed the pin on the right side, stowing the pin in the toolbox and presto, now we have draft control for raking and other grading operations. Why would that pin be put in place, and shown installed in the photos that talk about the draft operation? Removing the right pin suddenly makes the two top link grease fittings have a purpose.

I could see pinning it for mowing only but pushing the draft lever all the way down disables the draft control sensitivity anyway.

 

[GWD]

A photo or drawing would help to understand a bit better.

I'd like to check my own M7040 out of interest. But the draft control has worked since it was purchased.

 

[fast*st]

GWD, hey thanks, your post on 3pt height adjustment was helpful, Looking at my top link bracket, there is an actuating rod on the left side, that goes to intersect just to the right side of the 3pt hitch elevation sense. The bracket for the rod on the left side has a notch for pin clearance. Stout pin anchors the shaft that holds the top link bracket, its what that bracket pivots on. Center of the top link bracket has a grease fitting and just to the right of that, I had a pin that was a bit bigger than 3/8 dia and 4 inches long, through the top link bracket and through the pivot pin.

Don't have a clear picture but there is one in the 3pt hitch pages in the owners guide.

A photo or drawing would help to understand a bit better.

I'd like to check my own M7040 out of interest. But the draft control has worked since it was purchased.

 

[fast*st]

Here is a picture of the top link attachment point. The top link had two pins in place, one a few inches to the left of the grease fitting, and one to the right that's been removed.

 

[Kubota Newbie]

Well, my M4500 has a different arrangement, but I suspect that what you are doing is disabling the spring tension mechanism for the draft control. Thus allowing it to work more easily/readily when any minor change in top link is detected. There should be some device in place to resist the movement of the top link mount, mine is a large U shaped leaf spring mounted sideways, almost looks like that one is supposed to be a torsion arrangement of some sort. It should take a pretty fair force to activate the draft control, my WSM suggests using a test bar about 4 feet in length to pry the top link bracket up or down. My draft control does not really seem to activate when using the scraper blade, but it's really obvious with the 3 bottom plow (too much so for my taste, would rather use the depth wheel and float it).

 

[fast*st]

Well with both pins in place, they're about 11-12mm dia, there wasn't even any rattle movement in the top link bracket. With the right pin pulled, there is maybe 10mm forward travel allowed.

 

[Gundoctor]

fast*st: I just had the dealer here to look at my M7040 that I have had about 1 year now. I have no Draft the same as your. I just went and look & my has the pin in. So I will take out. They have no ideal what is wrong. They told it was me. Bull Shxt to them.

David Pidgeon
New Haven, Vermont

 

[Kubota Newbie]

Well, I guess my question is; How easy is it to move it that 10mm? You SHOULD NOT be able to move it simply by hand. If you can rotate it by hand that much without any pry bar you have something unhooked that shouldn't be.

BTW, 1100 or 1300???

 

[fast*st]

Well, its movable by hand with the pin removed, with the pin in place, the draft control is non operational. Unless that big center pin has some torsion operation. With the pin removed, the draft control operates what I'd call correctly when pulling a york rake, on the lightest settings it'll just skim the ground and as you push the draft down it'll take a bigger and bigger bite until its full down and rolling a full bite of dirt. Unless that center pin has some ability to twist, I couldn't get to move with any amount of force. If it was supposed to torque twist with both pins in place, why would there be a grease fitting on the end and in the middle. With the position of the three pin holes, low mid and upper, the upper is almost lined up with the centerline of the axis of pivot. With a 1 inch lever arm on a solid 1 1/8 torsion bar that's less than a foot long, force to rotate would need to be about 233,000 pounds. Not sure the top link pins would support that.


St1100 x2 97&99 'A'

 

[Kubota Newbie]

I'm betting the pin isn't full thickness all the way through.
I know that my Draft Control works on my M4500, I can not move my top link mount by hand (it'll wiggle a little but that's just wear). My owners manual suggests "position control" only for light implements like scraper blades. Mixed position/draft or draft control is suggested only for heavier ground engaging implements like a plow, or implements that are designed to pull deeper in the soil like a sub-soiler. There has to be some sort of spring resistance in that top link mount.

Mine is an '00, great bikes, a little heavy, I need tires though.

 

[GWD]

OK, I finally had time to investigate that pin and if it is necessary.

(Aside: The photo of your draft control linkage shows the middle hole is being used for the top link. Move it to the lower hole for more sensitive draft control.)

I tested my draft control on the M7040 by pulling the adjustment lever all the way to the rear to the most sensitive setting. Then a 4' crowbar was wedged in between the top link and the bracket. (You could just use the top link pin if you want.)

Pulling down on the crowbar caused the lift arms to raise very nicely. Letting off on the crowbar caused the lift arms to drop to their original position. This was all with the pin installed.

I weigh 200 lbs. and a 4' bar would make 800 ft-lbs of torque to actuate the draft control. I probably was using 100 lbs, or so. That seems about right since you want a the draft control to kick in at a fairly heavy load on a 70 HP tractor.

Remember, draft control should probably be more accurately called "traction control" since its main purpose is to keep you going instead of being bogged down by a plow, subsoiler, or other such drag.

In conclusion, with the pin in the draft control works perfectly. It appears not intended to be taken out. Without disassembling the linkage it is impossible to know if the pin goes through the shaft or whether it secures a spring or other torque-sensitive device.

Also, did you notice the linkage attached to the left side of the top link bracket with an adjustable turnbuckle? It did not seem to move when the crowbar trick was used but it must be an adjustment for draft control.

If you don't have a long crowbar then a steel digging bar could be used for the test.

 

[fast*st]

I did see that turnbuckle, perhaps its a multipart shaft inside, the pin had no resistance coming out or going back in, it'd be a snap to pull the other pin and take the shaft out to give it a looking over. Perhaps you are right and it just needs that turnbuckle extended a touch and I'd almost wonder if you could get two different ranges with it, pin removed would give a light sensitivity range and pin installed would be a higher force value. Moving light gravel with a york rake, pin removed and set in the middle of the draft range gave a nice rake job, and on the lighter setting it took a very nice controlled shallow cut. I'm thinking that even with the pin in the most sensitive hole, the york rake would have a hard time tripping it off. Adjusting the drop control and letting the draft regulate the upward adjustment ended up with a very nice raking job. But yes, pulling a harrow would best be done with all pins in place.

 

[GWD]

The key is that you are pleased with the results. Since the pin in question is loose, held by a hairclip, and is obviously made to be removed you may have stumbled upon a useful feature. It certainly is useful for your purposes so go with it.

I agree with the effect of the draft control with the pin in - it requires a lot of force to engage the draft control. A fully loaded heavy box blade will not engage it because there is not enough rotational force on the top link to activate the lever. It seems to need a longer reach into the soil like a plow, subsoiler, or middle buster (as already mentioned).

I had given up on the draft control as a leveling assistant but maybe now, with the removal of the pin, it can be a help. Hope to try it sometime.

 

[Gundoctor]

It would seem to me that someone at Kubota could and/or should have a answer for this. If I knew where / how to go I would do it. I ask my dealer but have not heard back .

David Pidgeon

New Haven, Vt.

 

[fast*st]

My dealer didn't seem to know anything about it, we're not really in farm country where folks do plowing with the tractor. But yes, happy with the fine control obtained with the one pin removed. I'll look monday but I do wonder if there is some type of a multipart spring shaft that would allow the holder to twist under load. Might be something else that's stuck.

 

[Gundoctor]

Sunday I removed my pin. My draft work for the first time. I have ask my dealer to contact the power-to-be at Kubota for more info on this. By putting a bar in the backet No 10 -#3C001-81803 the Draft bracket Rod and Turnbuckle moved which allowed the Draft to work. My arms went up over 12 inches highter. Maybe now I can lift my 3 Bottom Moldboard Plow more than 6 inches off the ground!!!!
If you go to Kubota's parts listing for M7040 and then to "3point Linkage/Drawbar Hitch" the K10500 Top Link Bracket - they show the parts. It is pin #050 that must be removed that allows #010 to move Draft rod .

I will update later.

David Pidgeon
New Haven, Vermont

 

[Gundoctor]

Here is the link to the Kubota Parts that I just explain about in the above post. I hope I can do this.

http://kpad2.kubota.co.jp/kpad2/PartsInfo.do?bookCd=100K5069&funcCd=&figNo=K10500&dispType=2

Dave

 

[fast*st]

Sunday I removed my pin. My draft work for the first time. I have ask my dealer to contact the power-to-be at Kubota for more info on this.
I will update later.

David Pidgeon
New Haven, Vermont

Thanks for the info and looking forward to an update from the big K

 

[Gundoctor]

I have had my dealer get back to me about this pin. I will enclose a photo of the parts he gave me.
The pin #050 SHOUND NOT BE TAKE OUT. The part #040 is a torsion bar as you can see slim down in the middle. This made to twist a lttle under load. Heavy load - more twist. He said the grease fitting #030 is there to keep filled so rust and/or water does not get to the #040 Bar so it can move under load.

Now look at the #140 turnbuckle. This he tell us this is used to get DRAFT to work right.

I hope this helps.

Dave Pidgeon
New Haven, Vermont

 

[fast*st]

I have had my dealer get back to me about this pin. I will enclose a photo of the parts he gave me.
The pin #050 SHOUND NOT BE TAKE OUT. The part #040 is a torsion bar as you can see slim down in the middle. This made to twist a lttle under load. Heavy load - more twist. He said the grease fitting #030 is there to keep filled so rust and/or water does not get to the #040 Bar so it can move under load.

Now look at the #140 turnbuckle. This he tell us this is used to get DRAFT to work right.

I hope this helps.

Dave Pidgeon
New Haven, Vermont

Thanks for digging, I'll see about adjusting that arm!