Wow, this thread has been ongoing for over 12 years! Many good advices here.
I am asking for help on behalf of my father: Recently he (again) broke a gear inside the K46 tranny (tried to pull a tonne of gravel up a hill). He dismantled it like last time, but this time around he had to dismantle the hydraulic engine as well, as the gear this time was the one attached to the disc brake, which is on the same axle as the engine.
I found the right gear for him and he assembled it on his own. Upon starting the engine and applying pressure on the pedal ... nothing at all happened, not even a tiny movement on the wheel axle. He was pushing forward and reverse quite a few times and then turned it off.
He dismantled all of it again, and realised that the small pin that supposed to lift the washer inside the hydraulic engine was missing - the one used to disengage the drive, and was later found at the bottom of the oil sump. So, he put back the pin and put all of it back together and tried again. Still no drive at all. After reasoning with him, we realised that with the pin missing, the drive should be working - it should be the other way around: Not possible to disengage the drive. So, the drive not working was not caused by the missing pin.
He dismantled it again and realised that the washer that the pin was supposed to push was missing. He just forgot to put it back the time before. He assembled it all again - still no drive.
I watched him following an instruction video on Youtube, and I could not see him going wrong anywhere, but the guy in the video mentioned something about the by-pass valves that I did not really got my head around. Mainly because I was not there when my father explained about a filter inside one of the valves.
I have a suspect that he might have lost some tiny part, like a ball inside a valve or something, but my workload is overwhelming me, so I do not have time to go there and have a look ... for the fifth time. Bless him, being over 80 years old, with an eyesight and hearing which have seen better days - I just wish he can get it working before I have to bring my own lawn tractor there, as the jungle is taking over their lawn more and more every day.
I have moved the transmission "backwards", i.e. turned the wheel axles, first one by one, then both, to test that the differential is working, and the transmission is working all the way to the hydraulic engine. From the other end, I have turned the belt wheel to confirm that the hydraulic pump is working, and it feels exactly as I expect it to do.
Are we just too shy when it comes to bleeding the pump/engine? Should we try for longer? When the (petrol-) engine is running and the forward/reverse pedals are pressed I can hear some kind of "rotating" sound from inside the transmission. Of course one would say, because something has to rotate inside as all is connected to the transmission.
I have read that some people first disengage the engine by pulling the thin thread-like handle that moves the arm and the pin inside the engine, push the forward/reverse pedals, and then re-engage the engine again, and repeat the procedure with the pedals. Would that make any difference?
Any thoughts, suggestions, or share your own aha-moments with me? I am out of clues now.
Thanks in advance //
Magnus