Leak at hst input shaft seal

[Zork]

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!

I missed some of this. If the input shaft is damaged at the seal location with a groove it will likely leak again if the seal depth isn’t seated to an undamaged portion of the shaft or if the shaft is not dressed with sand paper/emery cloth to smooth the groove- or you will need to install a sleeve and the new seal.

 

[JTKub]

Seems there are a few too many ex spurts on board already.

That's a fact. It's been some years since Ive been on TBN. I appreciate your advice.

 

[oldnslo]

Seems there are a few too many ex spurts on board already.

Ex = has been
Spurt = drip under pressure

I kinda resemble that remark

 

[Harry in Ky]

If the shoe fits....

 

[gpl2112]

To get that bearing out externally, I'm thinking you'll have to carefully use a pick and pry the inner race out, carefully get all the balls out, then pry the outer race out of the bore. Short of that, you'd have to disassemble the hydrostat so you could remove the input shaft out of the bearing, allowing you to press the bearing out of the inside of the front cover.

Thanks again to all for the replies. I was able to get the bearing out using a 3 arm puller I modified to wedge between the races...it took a few tries but I got it out. there was a huge amount of play in the bearing, I was able to get the new bearing in, and another new shaft seal. there was a decent amount of metal scraps attached to the drain plug magnet, I am assuming from the old bearing. I have the repair book for the tractor and taking apart the hst looks like a big job. I got the parts list for the hst from the parts guy at TYM. the shaft looks good from what I could see, no real damage. I am going to put the tractor back together and hopefully flush what I can from the system and fire it up.fingers crossed. I will report results,thanks again

 

[JTKub]

Good to hear you got it.

Must have been poor quality materials in the OEM bearing, or some type of defect in it that made it fail so soon. The fact you had shaft seal leakage sounds like it was getting lubed OK.

 

[gpl2112]

Finally had time to put the tractor back together and start it. Now I have more issues and therefore more questions. Before starting the tractor I noticed it. Somehow the 4 wheel drive shifter was pulled all the way back past the 4 wheel drive setting, It was jammed into place and I cannot move it forward. I am assuming it got moved back into that position before I put the back in. I did not notice.It was jammed so far back until I tried to put the cover over the shifters and it would not fit because the shifter was so far back. I started the tractor so that I could move it around to try to move the shifter. The tractor immediately began to move forward on its own. Is the four wheel drive shifter would not budge.Then the engine began to sputter and shut down. I try to adjust the speed.Pedal linkage to make the reverse side raise up a little bit I thought maybe that was the problem, I did not spend a lot of time adjusting the pedals. Started it back up same thing happened with the moving forward, and not being able to move the four wheel drive shifter. The engine began to sputter and I shut it down Immediately And started looking for advice. Any ideas would be greatly appreciated.Thank you

 

[Harry in Ky]

You're getting deeper by the minute. The 4WD shifter, lever, gears, shafts, ETC will have no effect on the tractor moving on its own. The "starts, sputters, and shuts down" may be totally unrelated as well, too early to tell. The "moving forward on its own" sounds more like something out of place with the hydrostat itself. If it were simply pedal and linkage related I would think you would be able to feel that in the pedal travel with engine off.

I have to wonder how did all that work before you took it apart?

 

[JTKub]

Assuming you had to meddle with the 4wd linkage to get the hydrostat out and back in there, I'd retrace your steps on that.

The hydro creeping forward sounds linkage related (definitely been meddled with). Does it go in reverse and seem to have full speed in reverse?

 

[Jake99]

On a hydrostatic drive system, the pump only can produce flow in any direction when the "swashplate" and thus the barrel is off center.
When the swashplate is center, the pump only spins but no flow is created
As far as i know these are simpel mechanically adjusted drive pumps.
AS JTKub mentioned, strip all the linkages.
Any Photos of the pump ?