BX24 HST Dip Stick Blew Out

[thavil]

Did a search but didn't come up with anything. This is my first issue with this tractor after owning it for 3 years.

After restarting my tractor in my garage, after removing my FEL, I backed out and noticed a trail of fluid. My HST dip stick was gone. I found the dip stick in the horse paddock area where I started removing manure. I figure that I worked at least 45 minutes with the dip stick out. During the 45 minutes, I was cleaning up more manure and turned my manure pile. No dust at all today since we had pleanty of rain recently. After cleaning the dip stick, I checked my fluid level and it's still on the full mark. I started the tractor up and parked it back in the garage.

Two questions:

1. 99% positive that the dip stick was fully seated before I started. Could there be some issue that would cause that much pressure to blow the dip stick out? Just before where I found the dip stick out, I installed the FEL and greased all of the zerks.

2. If this was your tractor, would you immediately change the HST fluid, filter and clean the strainer? Or since it wasn't dusty, what little may have gotten in there, the filter/strainer will take care of?

 

[pdowling1]

I would do nothing but check the vent for obstruction/blockage, and then go about my business. There is no real danger of contamination in that time and conditions. Changing the SUDT would seem foolish to me.

 

[EE_Bota]

I would be curious why oil was lost, but the unit is still full. Could it have been overfull? I agree on the vent issue.

I would not change the oil over what you described.

 

[thavil]

Thanks for the responses. After pdowling1 posted, I went though my workshop manual and couldn't find any reference to a vent. Finally, I found an old post that mentioned that the little red button just above the rear PTO is the HST vent (always wondered what it was). I will check it in the morning. Not sure what to check for since the button appeared to be clean when I looked today. Is this a push button?

EE Bota - Only a small amount of fluid was lost in my garage. From what I can tell, it only lost some fluid during the startup after dropping my FEL and while backing down my ramp from the garage. I checked the fluid before the first startup today and it was at the high mark of full.

 

[EE_Bota]

Thanks for the responses. After pdowling1 posted, I went though my workshop manual and couldn't find any reference to a vent. Finally, I found an old post that mentioned that the little red button just above the rear PTO is the HST vent (always wondered what it was). I will check it in the morning. Not sure what to check for since the button appeared to be clean when I looked today. Is this a push button?

EE Bota - Only a small amount of fluid was lost in my garage. From what I can tell, it only lost some fluid during the startup after dropping my FEL and while backing down my ramp from the garage. I checked the fluid before the first startup today and it was at the high mark of full.

I think the vent is not pushbutton. I don't have your exact tractor though.
I think I might affix someting to the stick to keep is with the tractor in case it tries the same trick again...I would hate to lose the stick and not be able to find it.

 

[Skyco]

Puzzling...the dipstick on my BX24 is pretty dang hard to pull out...can't imagine the pressure it would take to blow it out....

 

[thavil]

Here's what I did today to try and figure this out:

1. As EE Bota suggested, I tied the dip stick to the frame of the tractor. Back when I was in the Army, we called this an idiot cord.

2. Checked the red vent button again and nothing around it.

3. Checked the fluid level before starting the tractor and it was on the high full mark. Using an extractor, I removed enough fluid to bring it to the middle of the full marks.

4. After mowing my back yard to get the tractor warm, I checked my HST relief pressure and it meassured 1750 psi. The low end for this model is 1778 psi and the high end is 1849 psi. Last year, I had bumped my pressure up to 1800 psi but today, it read 1750 psi.

5. While dragging manure in the paddock area today, I remembered what may have caused the issue. Yesterday, I had backdragged manure and created a line to scoop up with my FEL. At the end of the manure line, I got off the tractor to kick the rest of the manure into the bucket. The lip of the FEL wasn't even to the ground, so I jumped on the tractor and moved the FEL control handle to the right for the dump position. The bucket didn't move and I released the handle. I tried one more time to dump the bucket and again, it didn't move (this is when I think the dip stick blew out). I then realized that I had too much downward pressure already on the FEL so I raised the bucket a few inches and then I could dump the bucket the few inches I needed to get it level.

Does this sound possible? Shouldn't the relief have kicked in to avoid this? If so, is there something I can check myself besides just looking at a red button that is the pressure relief. I really don't see what it's supposed to do.

 

[Skyco]

The "red vent button" is not a button- it is just a breather as Kubota calls it in the parts book.

 

[pdowling1]

The red cap is just there to keep water/debris out of the vent. If the dipstick was properly seated it seems impossible to me that you could develop adequate pressure to blow it out. You would hear the vent whistling before that happened. I have a nickel that says it never happens again!

 

[EE_Bota]

The red vent just "breathes." As the fluid heats up, it expands a bit, and if not for the vent, pressure would build in the transmission, likely challenging things like axle seals.

I think the "idiot cord" is a great idea, and I may add one myself, in the event that I pull the stick and forget to put it back or something.

To me, if the fluid level is right, and the vent can "breath" it is an absolute fluke, with virtually no other reason that the stick can blow out. Therefore, I will not be taking the nickle bet, since I expect to lose.