Any help would be greatly appreciated. I have a TYM T234 hst. Great little tractor.. I believe we bought it in 2018 or there about. Last year, I noticed very slow leak. From what seemed to be the input shaft to the HST just above the filter. Was very slow so I put it off.. I definitely thought that it was the input shaft seal. This Spring it got noticeably worse. So I took the body off and replaced the input shaft seal. I did it very carefully.. I put the thing back together and the leak is the same. I took out the section filter.It did not look bad.There was some debris I took out the suction filter. It did not look bad. There was some debris on it .when I took the first shaft seal out, It did not look bad. But I replaced it anyway. Could there be Any other causes to this issue? From what I have read, people have said it could be a pressure issue. Any ideas or a way to troubleshoot this? I would really appreciate it, thanks!
JTKub
Veteran Member
Could the leak be coming from somewhere else?
Does the input shaft look like it's running true? Just wondering if shaft wobble could be causing the input seal to leak.
Does the input shaft look like it's running true? Just wondering if shaft wobble could be causing the input seal to leak.
Thank youFor your reply. The only way I am able to see the shaft spin at this point is from underneath when the engine is running. it spins very fast, It's hard to really see if it's wobbling.. .. when I had the seal out, there was really no play with the shaft.. I did inspect the shaft itself and it was clean.I now realize I forgot to mention that it only leaks when I am driving the tractor not when it is parked and the HST is in neutral. When it leaks it splashes around under there and it's hard to tell exactly where it's coming from. But I can see some oil dripping from where the shaft is. I did check Some of the hydraulic pipes Just to see if they were loose. I did not find any loose fittings.. I had the idea to put a camera under there...and After it was all cleaned up, to see exactly what happens when I drove forward a little bit. It's just so congested under there,it's not easy at all to do that, With what I have. I am attaching.
A photo of the suction filter. It doesn't
Seem terrible to the point where it would back the system up, but I'm not a mechanic. Thanks again for your help.
A photo of the suction filter. It doesn't
Seem terrible to the point where it would back the system up, but I'm not a mechanic. Thanks again for your help.
Attachments
JTKub
Veteran Member
If its leaking at the same rate and area as before the seal change, all you can do is keep cleaning the area and hope you find the exact area of the source.
oldnslo
Super Member
A possible option is to add some fluorescent die that is visible via a black light. If like my Branson 2400H it is indeed difficult to see up in that area. On mine I can remove the floor board which helps some.
The dye and removing the floor board if is an option might help find the source. Can you tell if leaks only going forward or reverse or anytime it is moving?
Possibly put range selector in neutral and drive a little, then check for leak.
Good luck
The dye and removing the floor board if is an option might help find the source. Can you tell if leaks only going forward or reverse or anytime it is moving?
Possibly put range selector in neutral and drive a little, then check for leak.
Good luck
Thanks again for the replies. Just a couple more questions...is it more likely the leak is from somewhere other than the shaft seal because it does not leak when not driving, and the shaft is spinning no matter what? also is there a way to spin the hst shaft by hand if I remove the drive shaft itself? I could not turn it when I replaced the seal. I had read somewhere about a plugged return line as a possible cause, but everything works fine aside from the leak. thanks.
Attachments
oldnslo
Super Member
You might be able to put a vise grip on the input shaft and spin it. Not sure how your HST is built since some have external charge circuit and some have a built in charge pump. I wouldn’t want to spin it for any extended period of time with charge pressure in the loop.
Doubtful problem is blocked return line since flow would be in that line whenever the engine is running. Could be a plug on housing that sees pressure when the tractor is moving forward or reverse.
Doubtful problem is blocked return line since flow would be in that line whenever the engine is running. Could be a plug on housing that sees pressure when the tractor is moving forward or reverse.
JTKub
Veteran Member
The shaft between the engine and the hydrostatic drive is going to be directly coupled to either the flywheel side or crank pulley side of the engine. You're going to spin the engine over if you try to rotate the shaft.
Hi again, So I took the tractor apart again. I was able to get a video of the shaft spinning. It did look a bit wobbly to me. And I could definitely see the leak when I pushed on the forward pedal. It was coming directly from the center of the shaft seal. It is so hard to work where the HST is. I took the whole HST unit off. I was able to get the seal out again. And decided to do something that I didn't do thoroughly before. I took a good look at the bearing. It looks like the bearing balls themselves are very worn down and have a lot of play in them. I think that is the problem. If I get the bearing out, I can look a little deeper inside the hst. But I'm pretty sure the bearing is at least a big part of the problem. My question I am including a couple pictures and I cannot find any tool to help me get this.Bearing out it is very My question I am including a couple pictures and I cannot find any tool to help me get this. Bearing out it is very tight. Also need to put the new one in. Anyone has any suggestions? Please let me know. Thanks a lot.
