3point problems when using a jib crane

COclodhopper

New User
Ford 601 tractor. I put together a jib crane for the 3 point to move some things around. It is essentially configured like this: www.youtube.com/watch?v=FnP5YKiI5zk. The lift arms are not working as I would expect with the crane is attached. They do work correctly for other attachments.

If the crane is attached to the top most top-link location, raising the lift control handle will cause the lift arms to go to the top of their range and stay there. No height control. Drop the lift control handle to the bottom and the crane will crash down to the ground. So all the way up or all down, no control. If I connect the crane to the lowest top-link pin location, the crane will raise all the way up and stay there, no way to get it to lower as long as there is a load on the boom. Get the load off and it will release and crash to the ground.

I am not clear on how the draft control works, I havent needed it, but could this be causing my issues. Normally the attachments are pulling down or back on the top-link connection. But the crane is pulling up, so pushing the draft control rod inward. I have tried the draft control handle in both positions with no change in behavior when the crane is mounted.

The crane is essentially unuseable with the behavior of the hydraulics. Hoping someone has a suggestion. Thanks for the help!
 

couple of thoughts...

are you in draft mode, as that is exactly how it works.... flip the little lever under the position lever..... to full upright position, to put it back into position mode.

If in position mode and it does this, then....
check to see if someone replaced the rear most seat mounting stud with a bolt. It originally had a long stud that went down into the back of the draft spring and limit the travel so that a heavy load did not push or pull the spring too far and put it in draft mode...

also see that the spring is tight with no play in it so that the draft control sensing rod is not overriding the position control.
 
I have the same problem. I made a similar style boom pole last week for the higher lift capacity. If I lift something heavy like my box blade it does exactly as yours. I think it has to do with the pivot point on the pole. Not sure how but it seems to change the leverage pressure from a standard 3 point hook up.
 
OK, dumb question.
Why would you even bring the draft control into the picture?
I've never once even thought about using it.
I might add I have a hydraulic top link that allows the boom to go higher and more important when picking up downed trees to go lower.

mvphoto60893.jpg
 
(quoted from post at 05:18:26 08/28/20) OK, dumb question.
Why would you even bring the draft control into the picture?
I've never once even thought about using it.
I might add I have a hydraulic top link that allows the boom to go higher and more important when picking up downed trees to go lower.

mvphoto60893.jpg


Michael's dad, I think that it is obvious why one would ask about the position of the draft control lever: the number of posts here asking "what is this lever for?"
 
(quoted from post at 17:24:28 08/27/20)
couple of thoughts...

are you in draft mode, as that is exactly how it works.... flip the little lever under the position lever..... to full upright position, to put it back into position mode.

If in position mode and it does this, then....
check to see if someone replaced the rear most seat mounting stud with a bolt. It originally had a long stud that went down into the back of the draft spring and limit the travel so that a heavy load did not push or pull the spring too far and put it in draft mode...

also see that the spring is tight with no play in it so that the draft control sensing rod is not overriding the position control.

I normally run in position mode, no reason for draft for what I do with the tractor. I did try changing the draft control lever, but it didn't change the situation. Draft on, or draft off, boom lifts to the sky.

Tractor has an aftermarket seat. I will have to check on the long stud idea.
 
(quoted from post at 05:18:26 08/28/20) OK, dumb question.
Why would you even bring the draft control into the picture?
I've never once even thought about using it.
I might add I have a hydraulic top link that allows the boom to go higher and more important when picking up downed trees to go lower.

Well, I bring it up because I am in position mode, but the tractor is doing things that suggest the draft mode is controlling. And I have no other ideas why it is happening.
 
Just thinking... I don't use or need draft. Is there a simple way to lock it out? Doing so would help me diagnose the problem and might become a permanent solution if it works.
 
(quoted from post at 12:31:30 08/28/20) Just thinking... I don't use or need draft. Is there a simple way to lock it out? Doing so would help me diagnose the problem and might become a permanent solution if it works.
did lock out by welding straps to seat mount & pining those to draft yoke. Been that way for several decades. Got tired of breaking draft plunger.
 

I can remember on a 3000, there were ""lock out"" washers to stop the draft from working.... as it would work in both the push and pull mode. But thats too many years back and things are too fuzzy...

back ...

would again suspect a problem with adjustments, wear, with the draft control spring, and plunger that is overriding position control. if I am understanding what your saying...
BUT...
I do remember when placing barn rafters with a3 pt jib crane, I would occasionally over load it and the 3pt would then ""lock"" in the up position.... and only...after killing engine, and letting pressure bleed off, it would finally return to normal operation. but I think I was ""jamming"" the unload valve and cocking it sideways in the bore???. This action is not the same as your describing???

Also worked on a 600 series that had the rear stud removed and everytime he drove through a dip, the upwards pressure on the rocker would completely lift the rotary cutter up to the top position... then after 5 seconds would lower it back down to position setting...
 
Please let us know when you figure it out

Bought a New Holland 450 sickle bar mower to put on the back of a 1964 4000.

It does the same thing as you're describing.

Got aggravated, quit fooling with it, decided I'll figure it out when I retire next year.

Fred
 
I forgot to mention my regular boom pole that uses the adjustable top link works just fine.

Can you post pictures of both your jib crane and boom pole mounted to the tractor? Maybe the geometry is just different enough between them that running with a shorter or longer top link might correct the problem?
 
".. as it would work in both the push and pull mode."
Do you mean that either pushing [b:24fe12aa76]or[/b:24fe12aa76] pulling on the top link attachment yoke would result in LIFT, when operating in DRAFT mode?
 
I'm not the original poster but since photos were requested here they are. The one attached to the tractor is a standard boom pole. It uses the adjustable top link and works fine. Just doesnt go as high as I need. The one on the ground is a high lift version. It will only lift a couple hundred pounds with misbehaving. Distance from rocker arm attachment point to the poles pivot point is 24 inches.
 
(quoted from post at 16:22:08 08/30/20) I'm not the original poster but since photos were requested here they are. The one attached to the tractor is a standard boom pole. It uses the adjustable top link and works fine. Just doesnt go as high as I need. The one on the ground is a high lift version. It will only lift a couple hundred pounds with misbehaving. Distance from rocker arm attachment point to the poles pivot point is 24 inches.

So are you trying to post pictures of the OP's tractor, boom pole and jib crane? If not, and they are of a different tractor, does the one in your pictures have the same problem?

If not, and your only problem is that it won't lift as much weight as to you want, it may just be that the longer arm, which is the only way to achieve a higher lift that I am aware of, moves the weight too far rearward to where the lift simply cannot lift as much as you would like. Simple physics of the length of the moment arm. Same reason you can break a stuck nut or bolt free with a breaker bar, the longer arm allows a smaller force at the end to impart a higher force at something closer to the pivot point. The upper lift arms are only so long, and they can lift a certain amount at the ends of the lower arms, but as you move the center of mass that you are trying to lift father and farther rearward, the less weight it is able to lift.
 
Something in the geometry that makes the lift do that and the load applied to the draft sensing spring. I have messed up 2 tractor lift systems with a post hole digger that has a weird attachment and it overloaded the big spring. I also have 4000 row crop that when I put enough water in my weed sprayer it will make it lift all the way up at times even though lever is not in that position. When I move lever to lower it, it drops as if the unloading valve has unloaded the pressure.
 
Something in the geometry that makes the lift do that and the load applied to the draft sensing spring. I have messed up 2 tractor lift systems with a post hole digger that has a weird attachment and it overloaded the big spring. I also have 4000 row crop that when I put enough water in my weed sprayer it will make it lift all the way up at times even though lever is not in that position. When I move lever to lower it, it drops as if the unloading valve has unloaded the pressure.
 

ford 3000, 4000, and 5000 will sense draft on compression of the hydraulic rocker OR on tension of the hydraulic rocker. Short equipment will normally push the top link INWARDS creating "compression" of the draft sense spring. Long equipment can pull the opposite way as it digs in creating "tension" or pulling out... on the draft spring.

Ford 3000 and 4000s ONLY.... can have a ""special spacer"" put in at the bottom of the draft spring so that it blocks TENSION as far as draft sensing. Manual says this is NOT available on the 5000. (see fig 135)


This will also explain why a long jib crane will pull tension on the spring, and depending on the adjustment, it can even force the lift to fully lift,, while in the "position" mode when loaded or over loaded due to the draft sensing rod being pulled or pushed too far.
 

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