3 pt load dropping

Ginormous · May 4, 2012

And did you check to make sure the hydraulic lift control handle isn't slipping?

Johndeere3720 · May 5, 2012

If it is the hydraulic seal it isn't to hard to replace. Do be aware that Deere does not supply the O-ring, I went down to Kubota and they had them in stock. It was a $3 repair that took me about 2 days to figure out. Once I knew it was the O-ring it only took a few hours to get everything disassembled.

I have attached a link to my thread about the repair, it should be very helpful. I also highly suggest draining your hydraulic fluid and cleaning the hydraulic screen while you are at it, inspect your transmission while you have everything opened up. :2cents:

http://www.tractorbynet.com/forums/yanmar/202252-169d-3-point-hitch-weak.html

clemsonfor · May 5, 2012

Johndeere3720 said:
If it is the hydraulic seal it isn't to hard to replace. Do be aware that Deere does not supply the O-ring, I went down to Kubota and they had them in stock. It was a $3 repair that took me about 2 days to figure out. Once I knew it was the O-ring it only took a few hours to get everything disassembled. I have attached a link to my thread about the repair, it should be very helpful. I also highly suggest draining your hydraulic fluid and cleaning the hydraulic screen while you are at it, inspect your transmission while you have everything opened up. :2cents:

http://www.tractorbynet.com/forums/yanmar/202252-169d-3-point-hitch-weak.html

Jake was who i was referring to, when i mentioned the thread about dissasembly and picture documentation. I just could not remember his user name. I just never remember the JD # after Johndeere.

Domush · May 6, 2012

clemsonfor said:
Because with the results he said its NOT the O ring on the piston. If you close the valve under the seat this takes out the valve on the 3pt and only leaves the piston O ring.

I don't see your logic on this one.

with engine running - closed the 'drop-rate' valve and stood on the lift arms as before - I could see no obvious drop after about a minute.

Doesn't closing the drop-rate valve create a vacuum?

If so, then with or without a bad o-ring there will not be a drop. I see that rate valve as closing off the top of a drinking straw with liquid inside it.. whether or not you have the bottom blocked, no liquid is going to escape.

If this isn't the case, sorry for adding confusion.

Also, I saw no mention of depth control so I guess that is not on this model tractor, but mentioning it again just in case it is and was missed.

284 International · May 6, 2012

The stop valve just closes the port for the fluid. It is the intake and the exhaust for the cylinder, so the only route for fluid (barring a crack somewhere) is past the lift piston seals.

The principle is akin to a hydraulic jack's screw valve. The lift control valve normally lets fluid in and out, but closing the stop valve blocks its output, which risks damaging the pump.

Domush · May 17, 2012

Any updates?

rtd · May 17, 2012

Thanks for all the responses.

I've been busy with other projects so this one has been on hold. I'll be back to checking it again, perhaps tomorrow. I want to be almost certain of the cause before I start buying parts or taking things apart.

SPYDERLK · May 26, 2012

rtd said:
Thanks for all the responses.

I've been busy with other projects so this one has been on hold. I'll be back to checking it again, perhaps tomorrow. I want to be almost certain of the cause before I start buying parts or taking things apart.

From your description it is not the seal in the lift cyl, but something upstream of it - like the position control valve. It is not maintaining position as it should even if there was some leakage. How does the fluid look? I would be tempted to try a fluid flush, esp if its been a while since you changed it.
.. Do you have Draft Control on the tractor?
larry