Ford 2000, 3-point leak down under a load

[TX Ford 2000]

Looking for some advice on where to start looking for problems in the hydraulic system. I have a 1965 Ford 2000 (3 cylinder, gasoline). The tractor has been sitting up for a while. The lift arms on the 3-point appear to work fine while not under a load. Once a brush hog is attached, it will lift and lower the implement. But if you try to hold it a a certain height, the arms will slowly lower until the rear wheel is on the ground. At that point, you can hear the hydraulics system giving it a bump every 5 seconds or so and it will keep the front of the brush hog of the ground, keeping it from setting it all the way down.

I changed out the fluid for the rear end/hydraulics. I am still learning about tractors and have a long way to go, but would appreciate any advice on where to start looking/working. Thanks.

 

[JMOR]

(quoted from post at 22:16:25 01/05/13) Looking for some advice on where to start looking for problems in the hydraulic system. I have a 1965 Ford 2000 (3 cylinder, gasoline). The tractor has been sitting up for a while. The lift arms on the 3-point appear to work fine while not under a load. Once a brush hog is attached, it will lift and lower the implement. But if you try to hold it a a certain height, the arms will slowly lower until the rear wheel is on the ground. At that point, you can hear the hydraulics system giving it a bump every 5 seconds or so and it will keep the front of the brush hog of the ground, keeping it from setting it all the way down.

I changed out the fluid for the rear end/hydraulics. I am still learning about tractors and have a long way to go, but would appreciate any advice on where to start looking/working. Thanks.

n your simple hydraulic system, you have a pump, connecting lines/passages to valves and on to the lift cylinder. You pump up the cylinder to lift the implement, then close the valve to hold the position. If there is a leak in the lift cylinder seals, connections, or valves, then it leaks off & your implement drops. Pretty simple, huh. Now, tracking down & fixing the leak is sometimes time consuming & can wear you down. The part of your experience where with pump running & still can't hold implement up means that the leak is so big that the pump has insufficient volume to make up the leak volume. This could be the result of a big leak or a pump that has worn to the point that it has very little of its original capacity remaining or a combination of the two.

 

[TX Ford 2000]

Thanks for the reply.

If I raise the lever that controls the lift arms all the way to the top of it's travel, it will lift the brush hog all the way up. At that point the hydraulics will leak off and lower a bit, and then the pump lifts it back all the way up again. So the pump will continually be bumping it back all the way up. It is when I try to hold the brush hog somewhere in the middle that it continues to leak off until the back wheel touches.

I have ordere a service manual for this tractor, and waiting for it to arrive. After reading some other posts about similar problems, I think I may remove the cover which will allow me to see the cylinder, and possibly see a leak.

 

[JMOR]

(quoted from post at 11:50:56 01/06/13)
Thanks for the reply.

If I raise the lever that controls the lift arms all the way to the top of it's travel, it will lift the brush hog all the way up. At that point the hydraulics will leak off and lower a bit, and then the pump lifts it back all the way up again. So the pump will continually be bumping it back all the way up. It is when I try to hold the brush hog somewhere in the middle that it continues to leak off until the back wheel touches.

I have ordere a service manual for this tractor, and waiting for it to arrive. After reading some other posts about similar problems, I think I may remove the cover which will allow me to see the cylinder, and possibly see a leak.

nce taken apart, leaks are very, very hard to find (no pressure, no leak). In order to maintain some set position, there is a feedback mechanism consisting of a cam and a "cam follower pin" & a few links, which senses the rotation of the lift arm shaft & when it senses that shaft rotating in the direction of lift drop, it commands the control valve to open & supply fluid to raise it back to original position & then closes the valve...........the leak continues & the fall/lift/fall/lift cycles repeat. The cam & pin are wear points as Ford did not see fit to provide any lubrication mechanism for these components. Guess you could say "lubricated for life" & end of life is defined as when it wears too much to function properly.

 

[TX Ford 2000]

Maybe the feedback mechanism is a good place to start looking . . . thanks.

 

[JMOR]

(quoted from post at 13:41:32 01/06/13)
Maybe the feedback mechanism is a good place to start looking . . . thanks.

erhaps, but you do have some kind of leak or it would hold any position that you set it, even with engine off. The cam/pin feedback control only has 1/2 inch movement from full up to full down, so you can imagine that it does not take a lot of wear to throw it out of adjustment. Pin is only 0.309 inch diameter & are often found worn almost all the way through.