Hydraulic Lift Adjustment Problem

[PMNJ]

I recently did a replace of most hydraulic components. When everything was put back together the hydraulics are serverly out of adjustment. The hydraulics will not lower until the control lever is an inch from the bottom of the quadrant. The yoke was tightened until there was no movement in the spring and it only moved the position up about another inch. I have also tried adjusting the quadrant by loosening the four bolts and it doesn't allow for much adjustment. We checked all the internal components and it all appears to be hooked up and working properly. Anyone have experience with this problem after doing a rebuild on hydros?

 

[JMOR]

(quoted from post at 10:57:59 03/30/11) I recently did a replace of most hydraulic components. When everything was put back together the hydraulics are serverly out of adjustment. The hydraulics will not lower until the control lever is an inch from the bottom of the quadrant. The yoke was tightened until there was no movement in the spring and it only moved the position up about another inch. I have also tried adjusting the quadrant by loosening the four bolts and it doesn't allow for much adjustment. We checked all the internal components and it all appears to be hooked up and working properly. Anyone have experience with this problem after doing a rebuild on hydros?

ead the adjacent post about draft control plunger plate. If that plate & the plunger wear such as to allow the plunger to rest further rearward than when new, then it can result in symptoms like you describe.

 

[John (UK)]

There should be some movement in the Draft Spring, it should not be completely tight. You must be just able to turn the Spring when you have a 2 bottom plow mounted and in the raised position. Take all the Draft Spring off and see if any of the components are damaged, like the tube down the middle of the Spring and some have a separate seat for the Spring, is this still there or has it broken up. Some also have the Tube and the seat all in one and the seat part may break off. Where the plunger Rod attaches to the linkage to the Control Fork, it can be worn or distorted through the Draft Spring adjustment being forced to turn when it is partly seized. The main Control Fork,has it been assembled correctly so that the bottom part it is solid up against the top part at the "knee" halfway down. The spring from the Lift Cylinder should hold it tight and the Control Fork should not bend in the middle normally. It can also be wear on the Top of the Control Fork at the point where the shaft from the Control Lever pushes on the Fork and it can also be the Shaft from the Lever being worn or both this shaft and the top of the Control Fork. If there is wear anywhere here the adjustment on the Control Lever would not be enough. The Top Cover needs to come off the check everything, you can't do this is it is still on the tractor. Don't forget to detach the Control Valve from the bottom of the Fork before you try to lift the Top Cover....John

 

[John (UK)]

You should also check that the key in the shaft at the bottom of the Lever is still in place and that it hasn't dropped out and the shaft has turned. this would alter the adjustment of the Lever...John

 

[AKNJ]

I am PMNJ's cousin and helped assemble the hydraulics. We replaced the control plunger with the 8N style as this website recomended. The original was seized and we were careful not to bend the fork inside. We ended up cutting it off. I took the control spring off and checked that everything can move freely. According to the parts book, the spring plates and everything else is there and intact. The joint at the knee in the control fork and upper lever is straight and is in contact with each other. It's almost like the plunger is too long and holding the tab the quadrant lever activates too far away from the quadrant lever. Has anyone had this problem when replacing the plunger with the Ford plunger? I did notice that it had a 1/4" thick circular boss which the original did not have. (where the plunger contacts that triangle rear plate with the three bolts when the implement is raised). The original was just a rod that had a trangular boss at one end with a hole in it. Unfortunately I already threw the old parts away.

I didn't check the key in the quadrant lever yet, but before we took this thing apart, it did not behave this way. I will check the key tomorrow and get back to you guys. It's the only thing left I could think of that would cause this situation, right. Thanks again!

P.S.One more question. The two prongs on the front side of the fork that the plunger attaches to are supposed to slide into the holes on each side of the cylinder, correct?