ZD 28 Hyd lift Valve

[Trkr]

My sister has a ZD 28 and when you raise the deck, and it gets to the top, you have to manually push the lift handle back to center, or you hear the pump still straining. Is this a detent issue in the valve, and will it hurt anything to keep using it like this? Thanks

 

[Dave_eng]

My sister has a ZD 28 and when you raise the deck, and it gets to the top, you have to manually push the lift handle back to center, or you hear the pump still straining. Is this a detent issue in the valve, and will it hurt anything to keep using it like this? Thanks

I do not know this machine but offer the following comments after looking at the parts illustrations.

The valve does not have a detent but rather a return spring. Likely the deck only raises while the control lever is being pulled.

Check for any binding or rusty pivots for the control lever.

A broken return spring is possible but not likely. In view of the small parts inside the valve, I suggest disassembly be left to someone experienced.

Operating with the valve needing to be pushed back once the deck is raised is not a good solution for more than a day or two as inevitably, it does not get pushed back and the system overheats because the relief valve is continually discharging fluid.

Dave

 

[Trkr]

I do not know this machine but offer the following comments after looking at the parts illustrations.

The valve does not have a detent but rather a return spring. Likely the deck only raises while the control lever is being pulled.

Check for any binding or rusty pivots for the control lever.

A broken return spring is possible but not likely. In view of the small parts inside the valve, I suggest disassembly be left to someone experienced.

Operating with the valve needing to be pushed back once the deck is raised is not a good solution for more than a day or two as inevitably, it does not get pushed back and the system overheats because the relief valve is continually discharging fluid.

View attachment 44188

Dave

Thanks, I'll check the linkage first. Looks fairly simple, one way cylinder. I see a poppet ball and spring also, looks like that might be simple to check if the linkage is free. Only drove the machine briefly, and noticed that. I'll check it out better this weekend, thanks for the pic.