The dozer in question is a D4C hystat. I was checking the oil level in the final drives and the one on the right side was full enough that oil poured out the filler plug when it was removed. The finals call for 50W and since it's not nearly as dark as 90W, I didn't immediately recognize that it was hydraulic fluid. But then I noticed the hyd oil level had dropped. It's apparently doing it even when parked because after I drained it down to level with the filler plug, I checked again the next day and it was overfull again. Has anyone ever encountered this problem before? Also, will it hurt to run it this way for short periods as long as I'm not doing heavy pushing? This is a farm dozer so I won't have a chance to correct the problem until the winter.
You will be okay if you keep the hyd oil from getting too low. If it leaks when shut down it must be the drive motor leaking. Later Bob
Our old 7E the trans oil 30 weight went into the finals. We just kept adding transmission oil until they filled completely up. Never fixed it. It ran that way for 20 years and likely still going.
Based on the symptoms you mention the most likely culprit is the shaft seal on the drive motor. It's #9 on the illustration below inside the red circle. Be aware that the leaking seal may be as the result of some more serious mechanical issue inside the motor itself. There's no way of knowing until you get the motor out. The leak will need fixing but so long as you're careful not to let the hydraulic oil level get too low it should be good enough to take you to the winter. You'll just have to keep a careful eye on oil levels. According to the Service Manual the preffered way of removing the motor is to first to remove the cab to get sufficient access. Apparently it is possible to do it without removing the cab but it requires some serious ingenuity and the use of a size #10 shoe-horn...........