BX2200 Hydraulic fluid coming out HST Vent?

[BxRich]

My BX2200 had a puddle of Hydraulic fluid under the rear end. After cleaning and checking everything it appears the oil is running down the sides of the HST and is coming from the top HST vent (out the two side threaded holes at the top of the HST). I looked through the manuals and diagrams, not sure 1) if there should be fluid in this section of the HST; and 2) If there is fluid in the front section how it is returned to the reservoir.

Any thoughts or suggestions would be greatly appreciated.

If it would help I can get some pictures to add.

Thanks,

Rich

 

[skipperbrown]

Are you sure you have the correct hydraulic fluid level? That stick is hard to read. I'd like to see some pictures if you can get them up.

 

[diesel85]

This is NOT normal.

I would check the fluid levels.

What kind if maintenance has this machine had (especially recently)?

As the other user said, yes, it's hard to see on the little dipstick.

A trick I use to check it is using a clean paper towel, I lay it on the towel to imprint it on the towel. Then I compare it to the two marks on the stick.

 

[BxRich]

I knew I left information out. There was no oil on the dipstick, the HST and steering were non-responsive. I filled it to mid-way between the two marks and the HST and steering are responsive now. It is still however pushing out a very steady drip that is coming from the two side holes at the vent on the top of the HST. I am including pictures as well, both pictures are from the right side (side with the control valve and pump).

 

[BxRich]

At the start of the season the hydraulic oil was replaced, a new filter was installed (Kubota brand), the pickup screen was removed and cleaned and new o-rings installed. Kubota SUDT was used for the Hydraulic oil.

Since that time it has only been used for mowing with the MMM about 5 times, total of roughly 20 acres. The grass was very heavy on one of the cuts, but otherwise normal and no sign of any issues.

There has been a small hydraulic drip for a while, at the steering cylinder in the front but it is never more than 1/2 inch around spot on the floor between uses.

I am likely a little OCD but I check the hydraulic fluid level (along with engine fluids) every time I use it. The last time the level was between the two marks on the stick, closer to the top (fuller) mark.

I did start it up this time before checking, trying to see where the fluid was coming from, uncharacteristic of me.

Also, in looking at the diagrams it appears the actual vent is in the center of the top, and that area is open. While I could not see any fluid coming from anywhere else, it may be possible that it is somehow getting in to the "moat" around the vent and coming out the two side holes. (somehow that seems like a poor description but it is the best I can think of at the moment). I attached pictures to my response to the prior reply.

Really appreciate all the time and assistance. The parts diagrams and workshop manuals are helpful in many cases, in this case I am either missing something or there is more to the story. I am not familiar with working on HST transmissions, I have a limited understanding of their function at best.

 

[Smokeydog]

Noted any more whine noise from the HST? Oil might becoming aerated from air inleakage on the suction side of pump. The oil has antifoaming additives but even a smallest air inleakage on the suction side of the pump can cause the oil to foam enough when running hard and be carried out the vent. Recheck filter, screen, oil cooler and any suction line connections for damage and tightness. Paying attention to hard line to rubber line connections. Low pressure and suction hydraulic lines leak much different than high pressure.

Had a small leak at one of oil cooler connections on the B26. Started small just to wet the area then latter to spot the floor when parked. Was also getting some increasing oil external from around the fill plug. Oil level ever so slowly going down. The oil cooler has metal to metal tube connections with o-rings and spring clips. Replaced o-rings and fixed the problem. Could not see any damage to the old o-ring. Seem to run with less HST whine.

 

[BxRich]

Thanks for the thought. I may pull the suction screen again and check it, also the rubber to hard lines in the suction line before the pump, There isn't much in the suction line, I don't think the BX2200 has an external oil cooler, as far as I gleaned from the manuals at least. It seems the majority of the cooling is from a little plastic fan attached to the drive line from the motor just before the HST that forces air circulation around the HST case which is finned.

Just an FYI, I am about 2 hours west of Knoxville.

Extra info added later:

The oil coming out the vents is not milky, nor "frothy".

There is a small wet spot at the bottom of the banjo for the suction line/filter screen. Not sure if it is blow-back from the fan or if it is indeed a poor seal. Will clean it off good and see if it recurs without running the tractor.

 

[Smokeydog]

BXpanded is located in west Knoxville just of I40. Have some good mods for the BX line of tractors as well as their famous Piranha tooth bucket bar.

That plastic cooling fan working correctly?

 

[BxRich]

The fan is working. I drained the fluid. Looked new. The filter screen was clean but one of the o rings was already brittle. Replaced o rings and reinstalled it. Put a new hydraulic filter on and filled with fresh oil. No change still pushing oil out the vent at the top of the HST.

 

[Smokeydog]

Frustrating and you have checked the obvious problem areas. *#!#*!.

When running at mowing rpm, is it possible to see or feel air pressure/flow coming from the HST vent?

Pto clutch slipping or brakes dragging?

Can you tell if it’s running hotter than before? Hard to gauge since there is no gauge.

Kubota dealer any help?

I’m going to be replacing a new Kubota designed pump suction line on my HST B26 tractor soon to hopefully fix similar problem.