Engine oil in transmission, L185

[Zoeper]

I wanted to spray my vineyard on a couple weeks ago. Two rows in I noticed oil bubbling out of the gear lever cups, engine dipstick and several other places.
The previously clean transmission oil was clearly contaminated with engine oil as it started getting a black tint.
I suspect that the hydraulic pump is pushing oil through its front lip seal and into the engine, overfilling the engine sump and overflowing (pushing through seal?)into the transmission case. Engine oil level is also too high, indicating a 2-way flow of oil between transmission and engine. (not just sump pressure pushing engine oil into the transmission)
I had water contamination in the transmission before with corrosion to lift cylinder as a result. I suspect other moving parts in the hydraulic system might have suffered a similar fate possibly resulting in stuck valves, flow, bypass or otherwise. Overpressure in hydraulic system due to defective bypass valve resulting.

Has anyone experienced something similar before? I will dig into it properly later this week when my holiday starts, but would appreciate some input or advice in the mean time.

 

[Russell King]

I had a leaking hydraulic pump seal on my L185. It over filled the crankcase but never the transmission oil. There was nothing making the transmission fluid dark nor did the transmission fluid level change very much.

I also had transmission fluid coming out of the shift lever area but that was at a different time and was due to the vent being plugged up by a dirt dauber nest.

 

[Zoeper]

I had a leaking hydraulic pump seal on my L185. It over filled the crankcase but never the transmission oil. There was nothing making the transmission fluid dark nor did the transmission fluid level change very much.

I also had transmission fluid coming out of the shift lever area but that was at a different time and was due to the vent being plugged up by a dirt dauber nest.

Thank you for the reply Russel.
I will replace the Hydraulic pump seal. I will also have a look at the manual and see what type of seal is used between engine and transmission. Since there was water in the transmission, It is possible that corrosion on shaft or seal damage there is allowing overflow from engine to transmission.
This tractor was in quite a bad state when I got it and I had the engine rebuilt at the time. For the last few years the tractor saw little use, but I also have to admit I did not give it all the TLC I would have liked to.
Hopefully I can get it to a good state again this holiday. I also have the top of the transmission housing off at the moment to go through all the valves of the hydraulic system.
I will update as things develop.
P

 

[Russell King]

Thinking about it some more, I don’t think that the engine oil can get into the transmission unless several seals have failed and the clutch area is full of oil (plugged drain).

The engine seal is in front of the flywheel, then there is the clutch assembly behind the flywheel and then a seal starts the transmission sump. So there is a portion similar to a car’s bell housing containing the clutch. It should have a open drain in the bottom that would allow any leakage to drain out unless it is plugged somehow.

I know that there is an opening near the brake pedals with a cover to allow greasing of the sliding mechanism that carries the throw out bearing (not the bearing itself). You can look into that and see if it is flooded but I doubt that is the case.

Also the seal on the pump may be difficult to identify. There are three possible part numbers depending on the tractor serial number. But the pump may have been replaced by a newer (or older) model. I bought the “correct” one and it didn’t fit the pump. .So the point is you may want to order all versions of the seal unless you have plenty of time to wait on dealer to order it over.

There are also some o rings on the pump covers and inlets and outlet pipes you may want to also replace.

 

[Torinodan]

Water in that transmission isn't that easy to get out sometimes. It WILl foam up and expand and WILL want to come out everywhere. Happened to me. Had water in it, cleared it out, the vent was stopped up up. Get it hot, let it settle then drain the case, the axles drains, and clean the filter screen the best you can. I also put a hot halogen lamp under it with the cap off. Still has residue in it.
This is on a L185 as well.