Lift issues....

[joshbruce128]

Ford 851 Chattering....? Not sure the best word to use here. Chattering comes to mind. When lifting, my arms shake, chatter, shake as iff they were being raised over an enourmous file. I wouldnt descride it as hiccups, and it doesnt fall, it just.... chatters.... why?

-I rebuit the lift cover with new o rings.
-popped out lift valve and cleaned, not binding.
-popped out unloaded valve, replaced o ring, cleaned, not binding.
-Replaced worn control lever pin.
No bubbles in hydraulics indicating a leak or sucking air.
-When lifting, it's strong, lifts my 750lb mulch layer.
-I am pretty certain things are out of adjustment because when my control is halfway up, my lift arms come all the way up. Just not sure if the adjustment could cause the chattering. My gut says no, but I will be adjusting asap.

Any thoughts on what is causing this? I'm wondering if I have a bad or stuck ball in my pump, causing an uneven amount of hydraulic pressure when force is applied by the pump. But, I didn't see that as a possible cause in the IT manual, just my slightly educated guess.

 

[Old Ford Mechanic]

You need to tell us what tractor you are working on but, what you are describing is a classic sign of air in the system. If your tractor has a hydraulic pump mounted on the rear of the engine then here is the procedure i use to bleed the air out. On the end of the pump facing toward the front of the engine there will be a pipe plug that a 3/8 allen wrench will fit. With the engine running at idle speed loosen this plug until hydraulic begins to leak out. You should hear popping sounds as the air bleeds out along with the spewing of oil. When the spewing and spurting stops and you have a steady stream of oil then, retighten the plug. Your lift arms should now raise without chattering. If your pump seal is leaking the pump will continue to induce air into the system. The pump will need to be repaired. To clarify, The pipe plug for bleeding is located on the round body of the pump at or near the top side. It is not on the end plate at the front of the pump. Hope this helps you.

 

[joshbruce128]

You need to tell us what tractor you are working on but, what you are describing is a classic sign of air in the system. If your tractor has a hydraulic pump mounted on the rear of the engine then here is the procedure i use to bleed the air out. On the end of the pump facing toward the front of the engine there will be a pipe plug that a 3/8 allen wrench will fit. With the engine running at idle speed loosen this plug until hydraulic begins to leak out. You should hear popping sounds as the air bleeds out along with the spewing of oil. When the spewing and spurting stops and you have a steady stream of oil then, retighten the plug. Your lift arms should now raise without chattering. If your pump seal is leaking the pump will continue to induce air into the system. The pump will need to be repaired. To clarify, The pipe plug for bleeding is located on the round body of the pump at or near the top side. It is not on the end plate at the front of the pump. Hope this helps you.

Silly me haha, ford 851. I am familiar with the bleeding screw. Will give that a try. I assumed any air would be naturally worked out over time but this issue has been going on for a while so maybe not.

 

[Majorman]

Back in the day, middle 1960's, when we suffered from that problem on the Ford 2 and 3000's with the piston pump, Ford recommended using 1 gallon of Kerosene in the hydraulic oil, it had to be Kerosene not Diesel as that affected the "O" rings in the system. Later they brought out a Ford Blending Fluid, in gallon cans to use. More expensive than Kerosene of course. Do not know if they ever had anything like that in the US but it worked well for us.

 

[Keith Williams]

Ford 851 Chattering....? Not sure the best word to use here. Chattering comes to mind. When lifting, my arms shake, chatter, shake as iff they were being raised over an enourmous file. I wouldnt descride it as hiccups, and it doesnt fall, it just.... chatters.... why?

-I rebuit the lift cover with new o rings.
-popped out lift valve and cleaned, not binding.
-popped out unloaded valve, replaced o ring, cleaned, not binding.
-Replaced worn control lever pin.
No bubbles in hydraulics indicating a leak or sucking air.
-When lifting, it's strong, lifts my 750lb mulch layer.
-I am pretty certain things are out of adjustment because when my control is halfway up, my lift arms come all the way up. Just not sure if the adjustment could cause the chattering. My gut says no, but I will be adjusting asap.

Any thoughts on what is causing this? I'm wondering if I have a bad or stuck ball in my pump, causing an uneven amount of hydraulic pressure when force is applied by the pump. But, I didn't see that as a possible cause in the IT manual, just my slightly educated guess.

Josh,
I had the same problem. I took the pump apart and found broken springs that allowed the fluid to not be pumped smoothly.
There are 6 pistons in that pump that are pushed forward by a wabble plate and back by springs. As they go forward, the fluid is forced past check valves and pressurize the system. The broken springs did not close the check valves. So, the fluid forced out of some of the pistons did not go ahead but rather went back into another piston filling it from the pressurized side of the pump verses the low side.
I would almost liken it as to a miss in an engine. So instead of a steady flow, you get a pulsed flow that would be as you describe.
Hope that helps.
Keith

 

[joshbruce128]

Thats a great way to describe it. I'm pretty sure I have 2 problems, one being the adjustment and the second being probably the pump.

I have a remote kit arriving tomorrow so if I have the same "miss" using that ill know for sure its not in my lift but another finger pointing at the pump

Josh,
I had the same problem. I took the pump apart and found broken springs that allowed the fluid to not be pumped smoothly.
There are 6 pistons in that pump that are pushed forward by a wabble plate and back by springs. As they go forward, the fluid is forced past check valves and pressurize the system. The broken springs did not close the check valves. So, the fluid forced out of some of the pistons did not go ahead but rather went back into another piston filling it from the pressurized side of the pump verses the low side.
I would almost liken it as to a miss in an engine. So instead of a steady flow, you get a pulsed flow that would be as you describe.
Hope that helps.
Keith

 

[joshbruce128]

Josh,
I had the same problem. I took the pump apart and found broken springs that allowed the fluid to not be pumped smoothly.
There are 6 pistons in that pump that are pushed forward by a wabble plate and back by springs. As they go forward, the fluid is forced past check valves and pressurize the system. The broken springs did not close the check valves. So, the fluid forced out of some of the pistons did not go ahead but rather went back into another piston filling it from the pressurized side of the pump verses the low side.
I would almost liken it as to a miss in an engine. So instead of a steady flow, you get a pulsed flow that would be as you describe.
Hope that helps.
Keith

Went out and made my adjustments today, main spring was way out of whack, much better now.
With the tractor running at idle I loosened the bleeder plug on the pump and right about the time fluid started to flow out you could feel the pulsation pretty strong. That confirms to me that it is after all a pump issue. So, I'll be rebuilding that soon.

 

[Delion]

You need to tell us what tractor you are working on but, what you are describing is a classic sign of air in the system. If your tractor has a hydraulic pump mounted on the rear of the engine then here is the procedure i use to bleed the air out. On the end of the pump facing toward the front of the engine there will be a pipe plug that a 3/8 allen wrench will fit. With the engine running at idle speed loosen this plug until hydraulic begins to leak out. You should hear popping sounds as the air bleeds out along with the spewing of oil. When the spewing and spurting stops and you have a steady stream of oil then, retighten the plug. Your lift arms should now raise without chattering. If your pump seal is leaking the pump will continue to induce air into the system. The pump will need to be repaired. To clarify, The pipe plug for bleeding is located on the round body of the pump at or near the top side. It is not on the end plate at the front of the pump. Hope this helps you.

Is this the same procedure for a 3500 industrial?

 

[Sean in PA]

Is this the same procedure for a 3500 industrial?

If the 3500 has the the hydraulic pump mounted on the side of the engine and your problem is with the 3 point lift, then yes. If your issue is with the loader and/or backhoe hydraulics, then no.

 

[Delion]

If the 3500 has the the hydraulic pump mounted on the side of the engine and your problem is with the 3 point lift, then yes. If your issue is with the loader and/or backhoe hydraulics, then no.

Yeah mine is loader issue

 

[Sean in PA]

Yeah mine is loader issue

Start a new thread for your issue.

 

[joshbruce128]

Disassembled the pump look what I found... also the two rollers to the left appear to be from an old roller bearing that came apart an owner or two ago (current bearing is intact, to the right). Lucky me he left those spare parts in the pump for me. Oddly enough, the chunk of that plate is nowhere to be found, and no internal damage to speak of. Thank the old tractor gods for that.