D17 Series 4 3 point

I have a d17 series 4. 3 point will pick up anything I ask. But will not hold. It starts to bleed off asap. The remotes seem to work fine. I can open my round baler and the gate will hold until I actuate to close. BUt the 3 point arms will not hold.

Follow the hoses/lines that go from the lift cylinders to the lift valve section while standing at the rear of the tractor. That particular lift valve section has a rotary valve on the back of it that has a small tee handle. Tighten that tee valve as tight as you can clockwise with a vise grips. Take a larger diameter punch and strike the end of it and try and turn it again. If it moves at all, this may help your settling problem. Most tractors with that type of valve stack suffer a certain degree of settling. Some are worse than others. That is what the position control lever is for. When functioning correctly, the Position control lever will keep the 3pt from settling down.