3 point rising up

[Going4it]

WranglerX... I have the exact lever setup in my LX2610 for the 3PH. I also am a new tractor owner, 2 years now. So the hydraulic game is still new to me. I agree with you that fluid is leaking past a seal to raise the hitch, but would that cause the "lever" to creep forward/down?
I haven't had any problems with my tractor yet! But I do read through to learn.
Thank you all, for your input on various problems.

 

[TimberFarm]

If it makes you feel any better I just hooked up a 1,000lb hyd rear blade and it doesn't stay down.
Of course the ground is hard as concrete here. I just hooked it up and did a quick test run.

 

[GeneV]

Hoho223......Your operation is not the same as the MF GC series... It does not have a "joystick" but it has a control lever, pull up lever from "neutral" it raises 3PH hydraulically, press down from "neutral" the valve opens to bleed off hydraulic pressure and 3PH drops...

Sounds like to me 3PH ram has a leak past the seal(s) on piston and it allows fluid to switch side of piston and holds it up once ground contact has forced 3PH up.... Or control valve has a problem with leak through and actually holds 3PH up when ground contact forces it up....

If the o/p's report is accurate, this is the answer right there.

 

[DMW]

I have the same issue when using a rear snowblower, or boxblade at too little and angle. It is normal for GCs. Don't go spending money on something that isn't broke. OPs bracket solution seems like a good work around, rather than holding down the 3pt raise/lower lever.

 

[hube2]

I'm completely confused about how anyone could have a problem with the 3PT going up because the ground pushes the implement up on a GC.

The GC 3PT has a single-acting hydraulic cylinder. When you pull the lever to raise the implement a valve is opened to allow fluid to enter the cylinder from the pump. When you push the lever down to lower the implement it opens a completely different valve that allows fluid to be pushed out of the cylinder from the weight of the implement and this fluid flows directly into the sump. It is a fairly simple mechanism.

The only way that the implement can possibly go up is if there is fluid flowing through the valve that is actuated by pulling the lever up that allows fluid from the pump into the cylinder. If this valve is leaking then the implement would be continuously raising regardless of ground contact.

Because it is a single-acting cylinder, if the piston seal was leaking the only thing this could cause is the 3PT to drop when it shouldn't be.

 

[DMW]

I'm completely confused about how anyone could have a problem with the 3PT going up because the ground pushes the implement up on a GC.

The rear attachments can have a large footprint, it does not take a lot of pressure from it to open up the relief valve. It's not just the weight of the attachment, but the tractor pushing/pulling it at the same time. My rear blower doesn't have shoes, so it slides on the base . It will ride up on the snow as I drive backwards. Same result, the blower will raise, then I have to go forward, lower again, and continue on. Some attachments can produce a "rocking horse" motion going forward as well, same thing happens.

 

[knickerboch]

Thanks for the response, Hmm, ok so when I use the tiller I lower it down to ground and start moving forward, then it will on its own raise up a few inches, so I push the lever down again, if it gets raised up from going over a hump or pushed up by hard dirt , it won’t go back down, and will stay raised, so I’m either having to keep an eye on it all the time to make sure its down or drive with one hand holding the lever down, neither of which is a comfortable situation.

I had the same problem with my ford 1710 and the solution to this was to adjust the tension nuts on the linkage to the lever. Mine were frozen and I ended up applying heat to finally free them up. Hopefully yours won’t be frozen and penetrating oil will help with yours or they will be free enough that you won’t need either.

 

[GeneV]

I'm completely confused about how anyone could have a problem with the 3PT going up because the ground pushes the implement up on a GC.

The GC 3PT has a single-acting hydraulic cylinder. When you pull the lever to raise the implement a valve is opened to allow fluid to enter the cylinder from the pump. When you push the lever down to lower the implement it opens a completely different valve that allows fluid to be pushed out of the cylinder from the weight of the implement and this fluid flows directly into the sump. It is a fairly simple mechanism.

The only way that the implement can possibly go up is if there is fluid flowing through the valve that is actuated by pulling the lever up that allows fluid from the pump into the cylinder. If this valve is leaking then the implement would be continuously raising regardless of ground contact.

Because it is a single-acting cylinder, if the piston seal was leaking the only thing this could cause is the 3PT to drop when it shouldn't be.

I'm kinda hungover so am unable to currently think to hard on this, but I will say that a single-acting cylinder can function in a double-acting capacity via vacuum actuation.

I don't know the specifics of the valve on these machines, but I suppose a malfunctioning one may somehow produce a vacuum effect...not significant enough to affect raising the implement on its own, but just enough to retract the piston with aid of the implement being raised up when it bumps on a hill or whatever.

 

[JWR]

Hube2 said: "The only way that the implement can possibly go up is if there is fluid flowing through the valve that is actuated by pulling the lever up that allows fluid from the pump into the cylinder. " Not to take that out of context (and it may well be just our use of the English language?) BUT... taken literally that is not true. The 3pt can go up when lifted by a human hand or whatever force having nothing in the world to do with the lever. The mechanical restriction with any 3pt system is that you cannot push the implement DOWN unless the hydraulic control allows it, not UP.

 

[WranglerX]

I'm kinda hungover so am unable to currently think to hard on this, but I will say that a single-acting cylinder can function in a double-acting capacity via vacuum actuation.

I don't know the specifics of the valve on these machines, but I suppose a malfunctioning one may somehow produce a vacuum effect...not significant enough to affect raising the implement on its own, but just enough to retract the piston with aid of the implement being raised up when it bumps on a hill or whatever.

Hube2 said: "The only way that the implement can possibly go up is if there is fluid flowing through the valve that is actuated by pulling the lever up that allows fluid from the pump into the cylinder. " Not to take that out of context (and it may well be just our use of the English language?) BUT... taken literally that is not true. The 3pt can go up when lifted by a human hand or whatever force having nothing in the world to do with the lever. The mechanical restriction with any 3pt system is that you cannot push the implement DOWN unless the hydraulic control allows it, not UP.

Still digesting this but I really believe this is on track to what the problem is....