After repair of a brake failure and filling the transmission tank I immediately had oil draining into the inner final drive. The machine was never started. I removed and plugged the case drain line and it continued to drain . I removed the motor and the shaft seal had been damaged from heat, so that explains why oil was draining into the final. However, with the case drain not connected the oil ,it seems should not be draining into the case through the valve plate. The parts of the rotating group did not show signs of damage and all piston rings were intact. My question is , is this normal drainage through the flushing valve or a control port . It assume the flush oil should be checked. Any thoughts?
Can you clarify what you're saying is the issue? You're saying case drain line still plugged from motor and the transmission tank is still draining?
I guess my question would be "How much?" because those motors hold a fair bit of oil. The main pressure hoses hold oil as well, there may be a passage through the variable speed controller, don't know. I can't think of a way for oil to get from the pumps into the loop without pressure because of the charge checks.
It is draining a lot. I noticed oil running out of the inner final as soon as I finished filling the trans tank, I still had the drain plug out of inner final. At that point I capped the case drain line, Install plug in final , marked the site glass level . Left for the night. This morning it had about two or three gallons in the final. So I assumed I must have two issues , bad seal and loop leakage. Could not see any damage in the motor between the valve and head , valve and piston barrel or the piston rings. I may be chasing my tail, ESP if the proportional control is open to case in neutral.
I replaced the shaft seal and reinstalled motor. Tracks motors work as they should. So I suppose there is something open to case that is normal.
Um, It has been a while since I have looked at a crawler final drive but I do remember they originally came from the factory with 90W oil in the finals and Deere said that we could use hydraulic oil in them later on. So that being said. No oil should be transferring from hydraulic or transmission to the final drive cavity.
Agreed there should be no transfer from drive motor to final. The shaft seal that was damaged solved that issue. My concern was why I was still getting transfer prior to replacing the seal, but with the case drain disconnected . Other than the seal, the drive motor showed no signs of damage to cause excessive loop leakage. So I came to the conclusion that the leakage from the loop must be coming thru the variable controller. All this leakage was without starting machine and gravity fed. So far so good. I did put 80w90 GL5 in the final as the maintenance sticker recommended.