New Holland TZ24DA HST not moving forward or backward

[fogline]

Hi

I recently picked up a New Holland TZ24DA that was initially working. I ran it for about an hour on pretty decent hillsides mowing with a 4' brush hog. As I was going up a small incline it seemed to be slowing down and when I turned a corner, it just stopped. The PTO was still driving the mower and the power steering seemed to be working ok. Pushing both the forward and reverse pedals resulted in no movement other than some slight drifting downhill backwards.

I thought it might be a clogged filter so I dropped the top one that seems to filter to the hydrostatic. I have not replaced the lower filter yet. I did notice the fluid was not clean. I actually tried a filter I had here that was close but not right and much of the fluid dumped out into my bucket due to the improper seal.

Fluid level was topped before dropping the filter with no result.

Pedals seem to be moving / rotating shaft into the unit correctly.

I am wondering next steps. The trouble shooting talks about the pressure release valve as being a possible issue. Worried it is the HST itself, though the tractor only has 290 hours on it.

Appreciate any thoughts. Hoping I didn't buy a big $ problem.

 

[Yander]

Change the hydro fluid and filter per the manufacturer's specifications. I had one of those, and they are really nice little SCUTs, with Shubaura engines.

 

[fogline]

Change the hydro fluid and filter per the manufacturer's specifications. I had one of those, and they are really nice little SCUTs, with Shubaura engines.

Thanks, Yander. I did. No change in issue unfortunately.

 

[WM75Guy]

Does sound like a fluid flow issue. Here are the troubleshooting pages for my TC40DA HST from the service manual. May give you some ideas. It mentions a clogged suction strainer as a possible cause on mine, but I don't see one on the TZ24DA parts diagrams.

 

[Yander]

Make sure your 3pt is lowered all the way. My tractor once did this and I couldn't figure it out.

It ended up being a little low on hydraulic fluid and lowering the 3pt was enough to resolve the issue after adding a little fluid.

Then didn't have the issue again after that.

 

[fogline]

Does sound like a fluid flow issue. Here are the troubleshooting pages for my TC40DA HST from the service manual. May give you some ideas. It mentions a clogged suction strainer as a possible cause on mine, but I don't see one on the TZ24DA parts diagrams.

View attachment 5336665
View attachment 5336667

I was wondering about a strainer as well and it not showing up anywhere on the manual too. I saw something posted along these lines for a John Deere. The other thing that seems to keep being mentioned is the high pressure release valve. Do you have a diagram of where the strainer is on yours? Sounds like something that would dump all the new fluid if disconnected but at this point, with no progress, not sure what else to try.

 

[fogline]

Make sure your 3pt is lowered all the way. My tractor once did this and I couldn't figure it out.

It ended up being a little low on hydraulic fluid and lowering the 3pt was enough to resolve the issue after adding a little fluid.

Then didn't have the issue again after that.

Well. That was interesting.

I stood on the 3 pt to make sure it was fully down then got on and started the tractor. The fluid said it was at a perfect level still on the little dipstick. The tractor started barely creeping forward when I tried to drive it, initially moving a tiny bit, like and inch, then would not reverse. I tried upping the RPMs and got it to creep about a foot but still no reverse. I pushed the 3 pt up and down and rotated the steering wheel a bunch just to try to purge any air in the system. The tractor then would not move again and the fluid appears to be overfull at this point.

Thinking this is an improvement over no movement but seem to be back to that now.

 

[WM75Guy]

I was wondering about a strainer as well and it not showing up anywhere on the manual too. I saw something posted along these lines for a John Deere. The other thing that seems to keep being mentioned is the high pressure release valve. Do you have a diagram of where the strainer is on yours? Sounds like something that would dump all the new fluid if disconnected but at this point, with no progress, not sure what else to try.

It is a small strainer, no wonder it could clog and affect operation. It is buried on my TC40DA.

 

[dieselscout80]

It is a small strainer, no wonder it could clog and affect operation. It is buried on my TC40DA.

View attachment 5336753

Could you post the link to that diagram and parts page?

 

[Yander]

Did you buy a filter from a dealer for that tractor. I would ensure the filter is OEM for that hydraulic system, not a knockoff. Same with hydraulic fluid.

A case dealer or new Holland dealer. Case. Branded that same tractor.

If you used the correct filter and oil, you may have air trapped in the system.

 

[fogline]

Did you buy a filter from a dealer for that tractor. I would ensure the filter is OEM for that hydraulic system, not a knockoff. Same with hydraulic fluid.

A case dealer or new Holland dealer. Case. Branded that same tractor.

If you used the correct filter and oil, you may have air trapped in the system.

Any thoughts on how to purge the air from the system if this is the case? I was kind of wondering if the pump wasn't priming fully when it started creeping a little.

 

[Yander]

Any thoughts on how to purge the air from the system if this is the case? I was kind of wondering if the pump wasn't priming fully when it started creeping a little.

You can Google it also. The first thing you want to do is start your tractor and let it idle as your moving all hydraulic systems up and down. Loader 3 pt. -Point multiple times. Before you do make sure all hydraulic fittings are tight