Oil & Fuel Do Hydrostatic Transmissions of Kubota Tractors belch Oil all the time?

[JOHNTHOMAS]

I've bought 27 or 28 Kubotas and all were HST except for one B2300 and a mower model or two but the rest were HST and never had any ever leak. I have had a hose
or two that had a loose fitting that stopped leaking when I tightened it down and had a couple of hoses burst but never any burping or escaping from the transmission and I also attach and detach SSQA attachments hydraulicly controlled on my FEL on a regular basis with only moist with fluid when attaching or detaching the fittings.

 

[Smokeydog]

My friend’s had a problem on a low hour B26. Hydro oil coming out of the fill port at times. Not over filled. Took awhile to figure out. Slightly misaligned metal piping and rubber elbow to the suction side of the hydraulic pump on right side of the engine was allowing air to get sucked in when hot and aerating the hydro fluid. Doesn’t take much air to foam oil and cause it to overflow the fill port. Never leaked fluid at the rubber elbow. Had to slightly bend the the metal piping and replace the rubber elbow to fix and stays leak free now. Suspect a loose hydro filter or line connection on the suction side would cause the same problem. Checked my B26 and it had better assembly alignment. No problems on hilly farm.

 

[MechanicalGuy]

Here is the video and owner in question :


THREE REASONS NOT TO BUY A KUBOTA - YouTube

 

[MechanicalGuy]

I am missing what problem the YouTube video was referring to. Is there a link?

Up a post

 

[ericm979]

The front end loader, the rear three point, and any attachment run with the same reservoir as the transmission fluid. If you fill it up when the hydraulic cylinders are extended there is a possibility you have overfilled it and some transmission fluid might come out the back.

The amount of oil in the loader and 3pt cylinders is very small compared to the 10 gallons or so in the transmission. Setting the transmission level correctly with those cylinders extended should not result in a oil level so high that it comes out the overflow.

That does bring up a point though- it's not that hard to overfill the transmission that has the usual sight glass for checking the level. Many trans fluids are clear or nearly so. It can be difficult to tell if the sight glass shows no oil or it is completely covered with oil. Some people get fooled by that and keep adding oil. When filling the trans you need to slow down as you approach the fill amount and check the sight glass often.

 

[goeduck]

That problem in the video is absolutely not normal. A gallon a day? Wow!

 

[k0ua]

The amount of oil in the loader and 3pt cylinders is very small compared to the 10 gallons or so in the transmission. Setting the transmission level correctly with those cylinders extended should not result in a oil level so high that it comes out the overflow.

That does bring up a point though- it's not that hard to overfill the transmission that has the usual sight glass for checking the level. Many trans fluids are clear or nearly so. It can be difficult to tell if the sight glass shows no oil or it is completely covered with oil. Some people get fooled by that and keep adding oil. When filling the trans you need to slow down as you approach the fill amount and check the sight glass often.

Well I believe we disagree. Tell you what, how about some of the readers raiser their loaders, dump the bucket and raise the 3pt and report back to us how the oil level varies on the dipstick or sight glass?

 

[RickB]

The amount of oil in the loader and 3pt cylinders is very small compared to the 10 gallons or so in the transmission. Setting the transmission level correctly with those cylinders extended should not result in a oil level so high that it comes out the overflow.
.

I absolutely agree. Adding fluid to the full mark with loader raised, bucket dumped and hitch raised will add the lift cylinder rod volume times 2, the bucket cylinder rod volume times two and the hitch cylinder volume to the reservoir. That in no way will add enough to make oil puke out the vent.

 

[RickB]

Well I believe we disagree. Tell you what, how about some of the readers raiser their loaders, dump the bucket and raise the 3pt and report back to us how the oil level varies on the dipstick or sight glass?

Did someone claim the oil level did not vary under those circumstances? I must have missed that.

 

[crashz]

I agree with the limited visibility of the sight glass. I have a heck of a time seeing the level of fresh SUTD2 on the L2501 sight glass.

But to the original question, even on extreme slopes I haven't had any leakage. Purchased new and built to order in 2017, now at 120 hrs or so.