3pt hitch drops too low, gets stuck.

[shaeff]

Gotcha, basically just not allowing the lift arms to bottom out. I'm going to explore a few options this weekend- thanks everyone for the advice! It's much appreciated! I need to get this sorted out before our next snow storm. A 35 minute plow job turned into hours because of this!

 

[GaryLock]

I just rebuilt my 3pt cylinder on my kubota. On the push-side of my piston, there is a ridge, that i could see the mechanism getting hung up on, but it just bumps its way by it if dropped too low then raised. When I reassembled, I followed proper instructions for the spline and arms lining up at a 'dot' on the spline. Problem was that it would lift too high, and bump my seat, and in turn, not lower enough to drop my deck all the way to the ground. I was able to take off the two external snap rings and adjust the arms on the spline by one notch, which made everything perfect. Maybe look at your lift arms, and see if they use the same spline shaft mechanism. I have no idea if your setup if totally different, so it might be useless what I suggested, but I thought it was worth a shot. The other thing would just be using a check chain on the arms. Hope you figure it out.

 

[PatrickS2222]

Hi Shaeff, good to see you're back on deck. I've been a bit quiet recently, busy outside of an afternoon now that it's summer. Was reading the thread and as the idea was forming in my mind I read GaryLock's post describing a similar point. He could be right - the lift arms might just be one spline out on the rocker shaft. Your comment about the RH levelling box touching the axle housing when fully lowered is not abnormal - same on both my tractors and all similar models I've seen. I've never learnt exactly how the control side of the hydraulics actually works, so I'm quite puzzled how you can actually get it to work again from inside the lower housing. It sounds like something travels a little too far once fully lowered, and can no longer reach the linkage to move the control valve toward the "raise" direction. Lifting the arms only moves the mechanical components after the hydraulic cylinder, not the piston itself. Manually moving the valve (or the linkage to it) gets it back within working reach.
For the short term at least, moving the arms one spline might lose you a little lifting height, but get it to do what you want. :thumbsup: Alternatively, Coldsteelva's suggestion of a stop (even a small block of hardwood timber strapped to the axle housing) or your idea of travel-limiting chains will also achieve this. Be careful to ensure you use the triple-eyes on the rear housing, never the top link mount on these tractors - they can't handle much vertical or lateral force at all, only longtitudinal loads.
I'm going to have to fix my good friend's 35 hydraulics soon, so that could be rather enlightening! :laughing:

 

[shaeff]

I just rebuilt my 3pt cylinder on my kubota. On the push-side of my piston, there is a ridge, that i could see the mechanism getting hung up on, but it just bumps its way by it if dropped too low then raised. When I reassembled, I followed proper instructions for the spline and arms lining up at a 'dot' on the spline. Problem was that it would lift too high, and bump my seat, and in turn, not lower enough to drop my deck all the way to the ground. I was able to take off the two external snap rings and adjust the arms on the spline by one notch, which made everything perfect. Maybe look at your lift arms, and see if they use the same spline shaft mechanism. I have no idea if your setup if totally different, so it might be useless what I suggested, but I thought it was worth a shot. The other thing would just be using a check chain on the arms. Hope you figure it out.

Good point, my question is if this will simply stop the lift arm from contacting the axle housing, or if it will solve the problem. I'm trying to wrap my head around it- moving the lift arms on the splines won't change the overall range of motion, just the starting and stopping points of the arms. So theoretically, it could still bottom out like that but it just wouldn't be touching the axle housing? I'll have to get my repair manual back from my buddy and dig into it. (he's had it long enough anyway!)

Hi Shaeff, good to see you're back on deck. I've been a bit quiet recently, busy outside of an afternoon now that it's summer. Was reading the thread and as the idea was forming in my mind I read GaryLock's post describing a similar point. He could be right - the lift arms might just be one spline out on the rocker shaft. Your comment about the RH levelling box touching the axle housing when fully lowered is not abnormal - same on both my tractors and all similar models I've seen. I've never learnt exactly how the control side of the hydraulics actually works, so I'm quite puzzled how you can actually get it to work again from inside the lower housing. It sounds like something travels a little too far once fully lowered, and can no longer reach the linkage to move the control valve toward the "raise" direction. Lifting the arms only moves the mechanical components after the hydraulic cylinder, not the piston itself. Manually moving the valve (or the linkage to it) gets it back within working reach.
For the short term at least, moving the arms one spline might lose you a little lifting height, but get it to do what you want. :thumbsup: Alternatively, Coldsteelva's suggestion of a stop (even a small block of hardwood timber strapped to the axle housing) or your idea of travel-limiting chains will also achieve this. Be careful to ensure you use the triple-eyes on the rear housing, never the top link mount on these tractors - they can't handle much vertical or lateral force at all, only longtitudinal loads.
I'm going to have to fix my good friend's 35 hydraulics soon, so that could be rather enlightening! :laughing:

I've been wandering around for a bit, just been busy and not posting much! I have so many projects that there's hardly time to rest! I'm pretty sure Gary is right to an extent, as I'm remembering the splined shaft is slightly twisted. Maybe that's allowing the arms to lower more than necessary. I am on the same thought train as you, I don't understand what's happening inside to cause it to bump past it's workable area. It has to do something with the control valve sticking once the arms get too low. I need to look at the pictures I took of the underside of the hydraulic cover plate. I'm betting that something (maybe draft control related?) is not set quite right and causing this issue.

Once I pull the side cover, work the control valve by hand, I can feel it pop and as long as I have the position control in the raised or slightly raised position- the hitch will come up no problem. Not sure I have time to wrestle with the lift arms now, that may be a summer project.

I found sets meant for old Ford tractors that run "limiter" chains from the top link attachment point on the tractor to the lower hitch pins on the implement- in this case my snow plow. You're suggesting I forego the top link attachment and use the triple mounting spot? That shouldn't be a problem as long as the angle of the limiter chains is steep enough to pull downward rather than back toward the rear too much.

Here's a pic of one of the ideas I'm planning to fabricate, but instead I'll try the lower triple holes.

 

[PatrickS2222]

Good point, my question is if this will simply stop the lift arm from contacting the axle housing, or if it will solve the problem. I'm trying to wrap my head around it- moving the lift arms on the splines won't change the overall range of motion, just the starting and stopping points of the arms. So theoretically, it could still bottom out like that but it just wouldn't be touching the axle housing? I'll have to get my repair manual back from my buddy and dig into it. (he's had it long enough anyway!)



I've been wandering around for a bit, just been busy and not posting much! I have so many projects that there's hardly time to rest! I'm pretty sure Gary is right to an extent, as I'm remembering the splined shaft is slightly twisted. Maybe that's allowing the arms to lower more than necessary. I am on the same thought train as you, I don't understand what's happening inside to cause it to bump past it's workable area. It has to do something with the control valve sticking once the arms get too low. I need to look at the pictures I took of the underside of the hydraulic cover plate. I'm betting that something (maybe draft control related?) is not set quite right and causing this issue.

Once I pull the side cover, work the control valve by hand, I can feel it pop and as long as I have the position control in the raised or slightly raised position- the hitch will come up no problem. Not sure I have time to wrestle with the lift arms now, that may be a summer project.

I found sets meant for old Ford tractors that run "limiter" chains from the top link attachment point on the tractor to the lower hitch pins on the implement- in this case my snow plow. You're suggesting I forego the top link attachment and use the triple mounting spot? That shouldn't be a problem as long as the angle of the limiter chains is steep enough to pull downward rather than back toward the rear too much.

Here's a pic of one of the ideas I'm planning to fabricate, but instead I'll try the lower triple holes.

I understand your thoughts, but as I said I think they are intended to lower until they linkage contacts the axle housing. Moving the arms down one spline on the rocker shaft might reduce the lifting height, but it won't change the lowest height. What it will do is reduce the distance the piston moves forward in its cylinder, however I don't think the fault is there. I think you're also correct in suspecting an adjustment somewhere is not set correctly. I can't imagine where or why, but surely there are others who know a lot more about these machines than I do. Keep in mind the hydraulics plate and everything on it is standard equipment for a raft of models of the day.

Regarding limiting chains: Something similar to what's in your pics would be great. A couple years ago when our first dam was empty, I was removing the built-up mud from our first dam while I had the opportunity. To aid stability as well as grip, I had my slasher (bush hog) on the machine along with several 6-8ft lengths of heavy channel-steel - off-cuts from an industrial shed construction site. I put as much weight as it would lift, and it made a huge difference. The down side was the hydraulics were working hard just to hold the weight up - I presume the 45-odd year-old seals aren't what they used to be! After a couple hours the gearbox casing would be so hot I couldn't leave my leg touching it. As a temporary and experimental exercise, I made a make-shift chain set like those in your pics, around each lift arm once just aft of the lifting link, and double chains up and through two large "D" shackles in the outer triple-mounts. I hooked the ends together using a grab-hook which allowed me to set the length appropriately, then I let the lift down so most of the weight was on the chains. Worked ever better than I expected. This gave the hydraulics a much easier time, and the gearbox was then getting nowhere near as hot. I wish I took a pic, but I'm sure you can imagine my set-up.

On the tractor in the photograph - looks like a TEA series Ferguson or a Ford 8/9N? - it isn't as much an issue because the design in the area is different. But on yours, mine and all others with the same assembly, that top link mount cannot take much force in any direction other than in a fore-aft direction. This is important Shaeff ..... they break because it is not what they were designed for - that is why the triple- mount holes are provided, and any genuine MF implements such as cranes etc, my post-hole digger (a great asset for planting out larger fruit trees, grape vines etc I must be lazy .... no, our ground is so hard and dry) mount there. But seriously, in this pic you can just see the area. Imagine the upward force at that point and you'll understand what I mean.

 

[shaeff]

All very good points as usual! I'll definitely use the triple holes, I do agree there would be a LOT of force on the draft spring assembly with the limiter chains.

I grabbed some chain from the local hardware store yesterday. Tomorrow I'll fabricate some brackets to fit to the lower pins and to the triple holes. I'm going to look for a very long pin for those holes, or maybe a long bolt to mount the chain/upper brackets to.

And yep, I came across those limiter chains on an N board, I believe the machine is an N model.

 

[PatrickS2222]

Sounds good mate.

If that pin is missing from your tractor, this is what you need (cheap as chips), with a standard lynch pin:

S.71 Hinge Pin

Also Item 3 in this pic:

Bare Co - MF - Linkage Pins - Drawbars

 

[shaeff]

Sounds good mate. If that pin is missing from your tractor, this is what you need (cheap as chips), with a standard lynch pin: S.71 Hinge Pin Also Item 3 in this pic: Bare Co - MF - Linkage Pins - Drawbars

Perfect, thanks! Just curious what the significance of the hinged pin is? Does the hinged design serve a specific purpose?

Edit- never mind, I answered that question myself trying to use a long bolt with the hitch at the wrong height haha. Makes sense now!

Going to need to order one, my local tractor supply doesn't carry them.

 

[shaeff]

Well, today I found that limiter chains don't necessarily fix the problem. So now I'm 100% confused. I set them to stop the hitch from dropping too low (as a bandaid for the actual problem that I have yet to figure out) and I still had the issue while the plow and hitch were supported by the chains.

Also ordered a hinge pin so I can set the limiters up properly. Not that it actually matters now since the issue persists!

 

[PatrickS2222]

Well, today I found that limiter chains don't necessarily fix the problem. So now I'm 100% confused. I set them to stop the hitch from dropping too low (as a bandaid for the actual problem that I have yet to figure out) and I still had the issue while the plow and hitch were supported by the chains.

Also ordered a hinge pin so I can set the limiters up properly. Not that it actually matters now since the issue persists!

:laughing::laughing: Harry Ferguson's team thought of everything I guess! :thumbsup: Even the TE series and related models - 8N & 9N etc had that feature included on a very similar centre housing, although a shouldered version was used. I think it's shown in Bareco's pic. Non-genuine pins are very low-cost - just like most parts for these legendary models. The hinged area locates neatly in the centre mounting hole - deliberately wider to maintain the pin's strength. It should be tethered with a chain to a tag on one LH axle housing bolt, as should its lynch pin on the RH side. A pair of set-length stay-bars to hold the lower link arms at a set height - usually used with a nine-or eleven-hole flat drawbar - also mount there.

I'm also puzzled at why the 3PL gets stuck down. I'm also surprised someone hasn't chimed in with the solution, usually from also having had the same issue. That said, I've never heard of it before.