Hydrostatic drive pedal

joe putman · Apr 30, 2016

I have a 98' New Holland 1925 with 1300 hours. I am having issues with the hydrostatic drive pedal, but I dont believe the pedal is what is causing the problem. At times when i am dragging a blade or I have a good load in the bucket the pedal sticks. It has even frozen during normal use. The first few times it happened i didnt even know anything was wrong until i let off of the pedal but the tractor didnt stop. At times i can hit the back of the pedal to reverse the tractor and the pedal will disengage. Lately it seems to have gotten worse. Now in order to disengage the pedal I have to kick the brakes but this doesnt always work either. If i kill the tractor the pedal feels normal so i dont believe there is and issue with the actual pedal. Any ideas would be much appreciated.

Sprinklerman · Apr 30, 2016

I have the same machine , when was the last time you changed the hydraulic fluid and filter ?

Billrog · Apr 30, 2016

There's linkage that the return to center piston the peddle connects to that the little bushings could have a fair amount of wear with 1,300 hrs. You could also take the piston off and give it a going over as well. I had to do this with my last tractor every 12 to 1500 hrs. One of the holes in the linkage on mine also got fairly egg long from wear and I had to make up another one.

Sprinklerman · Apr 30, 2016

I think on my 1925 there was a piston behind the black covers under the steering wheel

joe putman · May 1, 2016

Thanks for the response. Previous owner said he had just changed fluids. I suspected he had not maintained ther tractor and I changed the oil but the New Holland dealer gave me the wrong filter. The fluid I drained looked good so I assumed the filter was new as well. I'll change it.
I'll also check the piston and bushings. I'll let you know what happens.

joe putman · May 24, 2016

Billrog said:
There's linkage that the return to center piston the peddle connects to that the little bushings could have a fair amount of wear with 1,300 hrs. You could also take the piston off and give it a going over as well. I had to do this with my last tractor every 12 to 1500 hrs. One of the holes in the linkage on mine also got fairly egg long from wear and I had to make up another one.

Thanks again for all yall's help. I removed the cylinder that returns the pedal to center but that didnt solve anything. I also disconnected the cylinder that is behind the pedal. I think the smaller cylinder behnd the pedal acts as a damper. Neither of these cylinders made much of a difference. As expected the pedal moves freely now with no resistance. When I started the tractor with both cylinders disconnected the drive pedal stuck in the forwad and reverse direction. When it did that i kicked the brake pedal and it disengaged the hydrostatic drive pedal. This doesnt work all of the time though. The linkage for the hydrostatic drive pedal goes down into the transmission so Im not sure what my next course of action should be.

Billrog · May 24, 2016

The cylinder should have a spring inside that gives you resistance and returns the pedal to center. I'm not familiar with NH tractors but for it to center they have to be hooked up with resistance in both directions with mine the springs never lost their tension but I had to clean them up and lube them. It was a while ago now but I'm sure I spent the day fooling with the system to get it working right again. There may be an internal problem but that's beyond my ability as with mine it was the warn linkage that was jamming up on mine.