Hydraulics on Farmall 656

[Bday]

Just put a loader on my 656. The rams up work fine, but coming down they jerk a little. The system makes a chattering noise. One guy told me it could be a weak spring inside one of the couplers. He said if the loader stayed at the hold position in float. Then the problem most likely was a coupler. Make any sense? Or should I start digging deeper?
Thanks , Brett

 

[J_J]

Switch the hoses from the bucket for a test.

Just reseating may help.

 

[Bday]

Switch the hoses from the bucket for a test.

Just reseating may help.

Hi JJ,
We switched outlets and still come up with same issue.

 

[J_J]

Another test to see if the valve is passing fluid.

Remove the QD's from the lift hoses and place in a bucket and see if there is flow from fwd and rev lever position .

Did the relief valve ever activate?

 

[Bday]

Another test to see if the valve is passing fluid.

Remove the QD's from the lift hoses and place in a bucket and see if there is flow from fwd and rev lever position .

Did the relief valve ever activate?

Not sure what you mean about relief valve activation. The loader jerks when dropping from raised position. We have down pressure to lift front end of tractor. Chattering noise comes when loader is lowered down. Since we switched outlets do you think it's in the loader?

 

[J_J]

Have you checked fluid level, or cleaned any screens or replaced filters .

Are there any air bubbles in the fluid? If so, could be suction leak.

The relief valve will activate when you have enough fluid and blockage to over pressure the relief valve.

Does your valve have load checks. If so, remove, inspect and clean if needed.

Install a 3000 psi pressure gage to the IN port of FEL valve and use it to monitor and trouble shoot the hyd system.

Erratic pressure is an indication of air in system, and also low fluid level..

 

[oldnslo]

A couple of questions:
Does it drop smoothly in float?
Does the loader chatter coming down slowly when empty?
Does the loader chatter worse when moving faster?
Does putting a load in the bucket make a difference?
Have you tried swapping the hoses on the lift function only? I.e. switch the raise and lower hoses. Does the problem still occur?
Does the same thing happen when to bucket dump when you have a load in the bucket and dump it?

Typically bad QD's don't chatter, they just totally stop all movement.

Are you using the valves on the tractor or is their a seperate valve for running the loader.

The fact that it raises fine would indicate the pump is functioning properly.

Jerky lowering sounds like either a mechanical bind or some form of pilot operated load device in your system. Not at all familiar with the IH 656 hydraulics so not sure what features they have.

 

[RickB]

The loader is dropping faster than your tractor's hydraulics can supply oil to the rod end of the lift cylinders. Adding an adjustable one-way restrictor to the lift cylinder's base end hose between the tee and QD male tip can help. Limit the return flow to the point where the cavitation is eliminated. A one way restrictor will not slow the lift function.

 

[Bday]

A couple of questions:
Does it drop smoothly in float?
Does the loader chatter coming down slowly when empty?
Does the loader chatter worse when moving faster?
Does putting a load in the bucket make a difference?
Have you tried swapping the hoses on the lift function only? I.e. switch the raise and lower hoses. Does the problem still occur?
Does the same thing happen when to bucket dump when you have a load in the bucket and dump it?

Typically bad QD's don't chatter, they just totally stop all movement.

Are you using the valves on the tractor or is their a seperate valve for running the loader.

The fact that it raises fine would indicate the pump is functioning properly.

Jerky lowering sounds like either a mechanical bind or some form of pilot operated load device in your system. Not at all familiar with the IH 656 hydraulics so not sure what features they have.

The loader drops slowly, smoothly if you ease the lever forward. If you push the lever too far forward the down action stops. Then use ease it back and it starts the jerky down motion. We did switch remotes same problem. It does it also when tractor is off and you drop loader to relieve pressure.

 

[J_J]

In float position full fwd, the ports on that spool are all open to tank.

If the lift arms stop lowering when you go to float, then the spool is not working like it is supposed to.

Remove the end cap on the the float spool and inspect and clean the float assembly parts. Check the spring center parts also.

All the float parts do is to keep the spool in a locked position, so all ports are open to tank, and the bucket follows the ground contour.

 

[oldnslo]

Have you used the hydraulics for any other implements recently? Did they work OK? From what you are describing it sounds like you may have a bad quick disconnect but I have never seen one that chattered before.

Can you swap the quick disconnect ends on the hoses for known good ones?

Rick B.
The loader is dropping faster than your tractor's hydraulics can supply oil to the rod end of the lift cylinders. Adding an adjustable one-way restrictor to the lift cylinder's base end hose between the tee and QD male tip can help. Limit the return flow to the point where the cavitation is eliminated.

Almost all farm FEL's will drop with the engine off so I doubt cavition is the problem here. It would take some large cylinders to crete enoughe surface area for vacuum to slow the fall of an FEL.

 

[RickB]

Have you used the hydraulics for any other implements recently? Did they work OK? From what you are describing it sounds like you may have a bad quick disconnect but I have never seen one that chattered before.

Can you swap the quick disconnect ends on the hoses for known good ones?

Rick B.
The loader is dropping faster than your tractor's hydraulics can supply oil to the rod end of the lift cylinders. Adding an adjustable one-way restrictor to the lift cylinder's base end hose between the tee and QD male tip can help. Limit the return flow to the point where the cavitation is eliminated.

Almost all farm FEL's will drop with the engine off so I doubt cavition is the problem here. It would take some large cylinders to crete enoughe surface area for vacuum to slow the fall of an FEL.

I didn't come here to start a debate. Cavitation of loader cylinders happens all the time. That is why regenerative circuits were developed and used by some manufacturers as a crutch. May well be happening here, maybe not. Don't dismiss it from the list of possibilities.

 

[Bday]

Got her fixed! I can't believe it. We changed the 2 main ram fittings and plugged everything back in, she works good now. Never would have that could be a problem! Thanks for the info guys! Check out the pics of the ugly beast on attachments later today.
Thanks! Brett

 

[J_J]

You said you changed the cyl fittings on one of them or both cyl and only that fixed the problem. Were the old fittings restrictor fittings?

 

[oldnslo]

Got her fixed! I can't believe it. We changed the 2 main ram fittings and plugged everything back in, she works good now. Never would have that could be a problem! Thanks for the info guys! Check out the pics of the ugly beast on attachments later today.
Thanks! Brett

Brett,
For clarification, what do you mean by the two main fittings? The quick disconnects, fittings in the cylinders, fittings in the valves, etc..

Glad it is working since thye sure do beat using a shovel for snow piles...

 

[Bday]

Brett,
For clarification, what do you mean by the two main fittings? The quick disconnects, fittings in the cylinders, fittings in the valves, etc..

Glad it is working since thye sure do beat using a shovel for snow piles...

The quick disconnect fittings on the hoses. Not sure if that was the issue, but it works now. I told my son I had never heard of getting issues from the fittings. So?
Brett

 

[oldnslo]

Brett,
What happens especially if the QD's are not the same style, (I.e. one half bal style and the other half poppet style) is with flow the poppet or ball seats blocking the flow. In your case the flow from the MT loader being lowered was juts right to close the poppet or ball and then allow it to reopen causing the pulsing or chattering motion. As you saw at higher speed the motion would completely stop which it what usually happens until the load is released or flow is stopped.

Out of curiosity where both halves of the QD's the same style?

 

[Bday]

Brett,
What happens especially if the QD's are not the same style, (I.e. one half bal style and the other half poppet style) is with flow the poppet or ball seats blocking the flow. In your case the flow from the MT loader being lowered was juts right to close the poppet or ball and then allow it to reopen causing the pulsing or chattering motion. As you saw at higher speed the motion would completely stop which it what usually happens until the load is released or flow is stopped.

Out of curiosity where both halves of the QD's the same style?

Yes, they were same style. We had to reconfigure the lines today. My son told me not to use the QD's that we had trouble with, but I did anyway. Put it back together fired it up and it wouldn't work. Tore it back down, put the QD's on we used to fix it the first time, and it works fine now.
The only thing I noticed was the spring pressure on the balls were stiffer on the QD's that didn't work. The good QD's were noticeably weaker. Crazy!

 

[oldnslo]

Yes, they were same style. We had to reconfigure the lines today. My son told me not to use the QD's that we had trouble with, but I did anyway. Put it back together fired it up and it wouldn't work. Tore it back down, put the QD's on we used to fix it the first time, and it works fine now.
The only thing I noticed was the spring pressure on the balls were stiffer on the QD's that didn't work. The good QD's were noticeably weaker. Crazy!

The heavier spring could cause the ball or poppet in the mating connector half to depress further and allow the ball or poppet in the heavy side to seat, thus stopping fluid flow. To check this would rquire taking some measurements on the two halves to determine if the weak spring side could travel far enough to allow the strong spring side to seat. Sure sounds like that is what is happening.

On the other hand, If'en it ain't broke don't try fixin it...

 

[J_J]

Those QD's should have been the first thing to check for this reason.

If the valve lever is in neutral, the fluid is blocked from the cyl.

When you push the lever down, you move the spool enough to release the fluid from the cyl, and if the cyl does not drop, then something is blocking or restricting the flow.

With lift arms raised, and engine off, if you push the spool lever down, or go to float, the lift arms will fall. They will eventually leak down anyway.