Grapple

[britej]

I purchased a EA wicked 66 grapple for M7060 and love it. Recently I bought a new deere 325G CTL-- but the grapple will not connect to the skid steer because the hyd hoses come out from the middle of the grapple. Of course, for the tractor that is not an issue as the arms are open between the plates, but the skid steer has a solid plate connecting the SSA plates. I replumbed the hyd hoses to the far left, by the left ram. It hooks up now, but when it opens or closes, the left side moves up much faster than the right side and same for closing it. Any idea how to fix this? I was thinking maybe a restrictor on the left ram? but have no idea how to size this. Any thoughts?

 

[TheOldHokie]

I purchased a EA wicked 66 grapple for M7060 and love it. Recently I bought a new deere 325G CTL-- but the grapple will not connect to the skid steer because the hyd hoses come out from the middle of the grapple. Of course, for the tractor that is not an issue as the arms are open between the plates, but the skid steer has a solid plate connecting the SSA plates. I replumbed the hyd hoses to the far left, by the left ram. It hooks up now, but when it opens or closes, the left side moves up much faster than the right side and same for closing it. Any idea how to fix this? I was thinking maybe a restrictor on the left ram? but have no idea how to size this. Any thoughts?

Is this a twin lid grapple?

 

[britej]

No, its the single lid.. has two rams, one on each end.

 

[TheOldHokie]

No, its the single lid.. has two rams, one on each end.

Should not happen. Check your plumbing - sounds like you have hoses crossed somewhere.

Dan

 

[GreensvilleJay]

does the oil go to the left side first and then tee off to go waaay over to the right or does the hose go to the center of the grapple, then equally travel left and right ?
supposedly it shouldn't matter(?) but... if the left ram gets a 'head start'....... ??

 

[North Idaho Wolfman]

Something is not adding up!
If it only has one Clam, how do you know one side is faster than the other?

 

[britej]

The hoses are plumbed correctly, however, yes, the left ram is getting a headstart. I can tell it because it is tweaking the top rake when it opens and closes. Those top parts flex... and it flexes a lot. If i barely move the rocker control, it opens level.. so i may be able to put a restrictor on the main line and it fixes it... i think the skidsteer just has too much flow and pushes too fast

 

[TheOldHokie]

The hoses are plumbed correctly, however, yes, the left ram is getting a headstart. I can tell it because it is tweaking the top rake when it opens and closes. Those top parts flex... and it flexes a lot. If i barely move the rocker control, it opens level.. so i may be able to put a restrictor on the main line and it fixes it... i think the skidsteer just has too much flow and pushes too fast

If the cylinders are in parallel and the rods are connected to the same rigid lid they should never move at different rates. They are self compensating by virtue of equalized base and rod end hydraulic pressures. If one cylinder pressure goes high it will stall and all flow will go to the other until the pressures equalize again. What happens if someone pulls and holds back against the end that moves first? That should make it stall and the other move. A picture of the cylinder hoses and routing would be informative.

Dan

 

[britej]

But yes, the main lines go to the very left of the grapple, as opposed to the middle.. and it splits and goes straight to the left ram and all the way over to the right. i wouldnt think it would matter... but it surely does... i guess the left ram is getting most of the flow and the right is getting very little.. but when i clamp, they both will crunch a log. I dont think there would be any issues if i could rig up a way to hook these hoses up from the middle, like it was designed.. but i cant.

 

[britej]

If the cylinders are in parallel and the rods are connected to the same rigid lid they should never move at different rates. They are self compensating by virtue of equalized base and rod end hydraulic pressures. If one cylinder pressure goes high it will stall and all flow will go to the other until the pressures equalize again. What happens if someone pulls and holds back against the end that moves first? That should make it stall and the other move. A picture of the cylinder hoses and routing would be informative.

Dan

That was my thinking as well.. the lid is all one piece, but it flexes, left side moves up faster when opening, almost dragging the right side up, and closes faster when closing, almost pushing the right side down. The left ram is getting much more flow because i have the main line basically plumbed directly in to a tee, that goes to the left ram, and to a line that goes all the way to the right. oh well, im going to try a reducer on the main lines, as if i barely move the rocker, they open at the same rate.

 

[TheOldHokie]

That was my thinking as well.. the lid is all one piece, but it flexes, left side moves up faster when opening, almost dragging the right side up, and closes faster when closing, almost pushing the right side down. The left ram is getting much more flow because i have the main line basically plumbed directly in to a tee, that goes to the left ram, and to a line that goes all the way to the right. oh well, im going to try a reducer on the main lines, as if i barely move the rocker, they open at the same rate.

Flow follows pressure so I am skeptical of that analysis. Restrictors are not the way to fix problems. Move the tees to the middle and equalize the legs if you think that is the problem.

Dan

 

[North Idaho Wolfman]

Sounds like if it never did it before you altered it, then the lines, or fittings that you've added have a restriction on the cylinder that's moving slower.

One other possibility is that the cover or cylinder has a bind on the side that's moving slower.
Disconnect the cylinder ends and see how it moves manually.
Could be it just has more wear or bind.

 

[TheOldHokie]

That was my thinking as well.. the lid is all one piece, but it flexes, left side moves up faster when opening, almost dragging the right side up, and closes faster when closing, almost pushing the right side down. The left ram is getting much more flow because i have the main line basically plumbed directly in to a tee, that goes to the left ram, and to a line that goes all the way to the right. oh well, im going to try a reducer on the main lines, as if i barely move the rocker, they open at the same rate.

What size hose on the grapple and what's the hydraulic flow on the skid steer. Does it behave the same on the tractor?

I have a twin lid and it naturally behaves this way but much worse. One will close completely before the other even starts to move. It takes some getting used to but it does not prevent it from working. Yours should be even less of a concern.

Dan

 

[GreensvilleJay]

hmm... what happens if there's a 'slug of air' trapped between the left and right cylinders. I've had that happen with the forklift where the 'slug of air' went back and forth in the brakes.
maybe it can't happen ? maybe between control valve and cylinders ?
jes thinkin 'outside the box'....

 

[britej]

Flow follows pressure so I am skeptical of that analysis. Restrictors are not the way to fix problems. Move the tees to the middle and equalize the legs if you think that is the problem.

Dan

What size hose on the grapple and what's the hydraulic flow on the skid steer. Does it behave the same on the tractor?

I have a twin lid and it naturally behaves this way but much worse. One will close completely before the other even starts to move. It takes some getting used to but it does not prevent it from working. Yours should be even less of a concern.

Dan

It works fine on the tractor, hooked up in the middle. The hoses are 3/8 to the cylinders.. and maybe 1/2 to on the main lines to the tractor. I wouldnt be too concerned about it if it didnt tweak the top rake so much.. and it may never hurt anything.. but it sure looks like it will tear something up. The reason i think a restrictor would help is if i barely move the rocker in the skid steer to open it, it opens slow, but level. I think my steer has 26gm low flow and 32 on high.. of course i only use the grapple on low. my tractor has 11 gmp.. I think it is just dumping too much volume and pressure and getting to the closes cylinder.. but, I like the idea that maybe there is an air pocket going to the right cylinder. I did think about that, but figured it would bleed itself off.. and it never fixed.

I replumbed the thing to stock and am only using it on my tractor right now.. but i really would love to have the option

 

[North Idaho Wolfman]

Leave it as is (plumbed as original and connected in the center) and add jumper sections to connect it on the skid steer on the side, and see if you have the same issue with the one side outrunning the other.

 

[TheOldHokie]

It works fine on the tractor, hooked up in the middle. The hoses are 3/8 to the cylinders.. and maybe 1/2 to on the main lines to the tractor. I wouldnt be too concerned about it if it didnt tweak the top rake so much.. and it may never hurt anything.. but it sure looks like it will tear something up. The reason i think a restrictor would help is if i barely move the rocker in the skid steer to open it, it opens slow, but level. I think my steer has 26gm low flow and 32 on high.. of course i only use the grapple on low. my tractor has 11 gmp.. I think it is just dumping too much volume and pressure and getting to the closes cylinder.. but, I like the idea that maybe there is an air pocket going to the right cylinder. I did think about that, but figured it would bleed itself off.. and it never fixed.

I replumbed the thing to stock and am only using it on my tractor right now.. but i really would love to have the option

If it works with the tees in the middle what prevents you from running the supply hoses out one side? That is exactly how my grapple is plumbed.

Dan

 

[britej]

If it works with the tees in the middle what prevents you from running the supply hoses out one side? That is exactly how my grapple is plumbed.

Dan

Just the way it is designed with the braces and the way the lines are ran in the C channel. it can be done, but will require cutting and welding a few braces and channels. but, that may be the only option.

 

[OldcrowP51]

You have air in the system.
The air bubble gets moved around when on the skid steer due to the higher pressure higher flow system.

 

[OldcrowP51]

With the hoses disconnected from the tractor try and lift the rake.
It should not move.