occasionally oil coming out of tranny vent B1750 hst on shutdown

Hello: This is my first post, hope it is done correctly. My tractor is a b1750 HST. Occasionally the transmission pushes oil out of the tranny vent behind the drivers seat when the tractor is shut off. I have made sure the fluids level is correct and not overfilled. Hope I get help from all of you and thank you for reading this.

Hi:This happens more in the severe cold weather, but will happen very rarely in the summer. The filter and oil was changed this summer. I did not notice if the oil was milky but the next time it happens I certainly will. the amount of oil is about one or two measuring cups in volume, it does vary. In the cold weather it does take considerable time for the oil to come up to a normal viscosity for efficient use of the tractor. I have a magnetic heater that usually goes on the block. I think I might try putting this on the tranny and see if the problems is mitigated. Thanking all of you again in advance.

Hello North Idaho wolf man:

As an added note to the above. When the fund was changed I did not flush out the gearbox. I have never done this and was hesitant. Would you suggest diesel or kerosene and would you recommend running the unit or not. I am worried about devarnishing the seals and having leaks. This tractor is old and I do not know the last time the gear box was cleaned or new seals put in. Thanks Grandkubota.

Thank you< I will run it with the vent out and the cover off for a few runs. Looking at the cover very carefully it appears the cover has 100 % contact with the block it sits on. There also appears to be a light coating, like maybe a few thousands thick of gasket( IE permatex) on the block. Maybe the previous owner did not understand the the function of this area and it has taken two years for the problem to re-surface. But then again maybe he thought sealing it was the easiest option to make the leak go away without fixing the root problem, if there is a root problem or just a poor initial design.
Thanks Grandkubota

Problem(s) solved. Several little things were a miss here 1) Both suction screens were not clean. The transmission one more so than the Hydraulic one. 2) Drained the oil and found it to be very thin and well used. Therefore not optimum for power and probably had no antifoaming agent left in it.3) several of the clamps on the suction side of the hydraulic pump, including the ones to the cooler were very slightly loose, maybe a full turn of the clamp screw. 4) did a settle test on the oil that came out of the mid PTO well after all oil drained through the Screen ports and found it to be contaminated with some water but not a lot. 5) the lift arms when they came up to the top position would hit a home made lever connected to the forward/reverse pedal. This would cause the machine to be constantly, all though very slightly, pushing the oil through the hydraulic motor causing undoubtedly excessive heat and oil degradation.

I corrected all of the above and then flushed the system twice with new TDH oil. It runs very well now on the hydraulic and transmission side.

Next is a rework of the glow plugs and the injectors.

Thanks for your info,
Grand Kubota