Leaking gear boxes on mower decks

[TJP440]

My departed GR2120 ( bought a new one) had developed the leaking gearbox seal on the mower deck. In looking at it I noted the breather valve had a 5 stamped on it. Removing the valve I noted that is was spring loaded and would require X amount of pressure to open (5lbs?). That coupled with the small vent holes that always get covered with clippings dirt etc. got me to thinking.
So, I replaced the vent with a backwards facing filter and a 90 degree elbow on it. Mowed 3+ Acres 4 or 5 times with no signs of leakage. Thought I would post it here and possibly help someone with a leaky box. The fitting is 1/8 NPT and the P-clamp was secured to top rear bolt on the gear box.
The filter was oriented with the direction of flow towards the rear and the elbow was added for a bit more protection.

 

[TJP440]

Wanted to up date this. The above mod worked well on level ground but would still puke a bit of fluid going down STEEP hills and possibly when mowing with the R side of the deck substantially lower (mowing a hill sideways). I have devised what I believe will resolve the issue permanently but need to test it a bit more to be sure. Will update

 

[D2Cat]

Wanted to up date this. The above mod worked well on level ground but would still puke a bit of fluid going down STEEP hills and possibly when mowing with the R side of the deck substantially lower (mowing a hill sideways). I have devised what I believe will resolve the issue permanently but need to test it a bit more to be sure. Will update

Why not put the original check valve in the hose where you have the filter? Wouldn't that allow less dirt in?

 

[whitetiger]

Wanted to up date this. The above mod worked well on level ground but would still puke a bit of fluid going down STEEP hills and possibly when mowing with the R side of the deck substantially lower (mowing a hill sideways). I have devised what I believe will resolve the issue permanently but need to test it a bit more to be sure. Will update

Why not replace the leaking gearbox seal, reinstall the original vent back into the gearbox, and be done with it?????

 

[TheOldHokie]

Why not replace the leaking gearbox seal, reinstall the original vent back into the gearbox, and be done with it?????

Too simple.

Dan

 

[TJP440]

Too simple.

Dan

not quite
The seal isn't the issue, it's the flipping vent/breather.
I'm not sure if it's the hilly acreage or the poorly placed VB.
The hills are one issue. The other, if one looks at the placement of the breather, it is just to the R of the gearbox shaft which can/ will throw oil as it rotates. If enough oil get's into the opening for the V/B it will start pushing fluid out. Couple that with the suggested UDT2 foaming you now have wet fluid on top of the Gearbox collecting everything it can.
Then as the fluid cools back down it will draw debris into the tiny vent holes plugging them.
We now have a non vented gearbox that will eventually take the seal out. It's a bad design that Kubota has ignored correcting.

 

[TJP440]

Why not put the original check valve in the hose where you have the filter? Wouldn't that allow less dirt in?

Probably not as the filter was holding about an ounce of fluid and it the check valve will still be in the same dirty environment collecting debris. The other issue is the check valves vent holes get plugged rather quickly.

 

[JasonW]

That machine specs UDT2 for the gearbox? I haven’t seen that before. Ones I’ve dealt with called for gear oil or 10w-30 motor oil.

Since you mentioned a foaming issue with UDT2 have you thought about using gear oil instead? You know for a gear box?

 

[TJP440]

I'm running 75-140 Synthetic gear oil in it currently. And yes it calls for UD2 in the mower deck gearbox.

 

[Henro]

I'm running 75-140 Synthetic gear oil in it currently. And yes it calls for UD2 in the mower deck gearbox.

Curious. Calls for, or as an option along with gear oil?