New here. I have an older (1998-2002) l4310 HST tractor. Tractor suddenly lost all forward travel but reverse works fine. I got the tractor for a very reasonable price and the problem was already present. Not super familiar with kubota hydraulics but do have pretty good nechanical knowledge. Not sure if there are separate relief valves for each direction of travel. Any help or direction to look in would be greatly appreciated.
L4310 lost forward travel
- Thread starter Rupert513
- Start date
Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
Why do people always think a hydraulic problem is the "relief valve"?
The first thing I woukd do is inspect the HST pedal linkage to see if its moving the HST vakve to the forward travel position.
Dan
Do download the WSM first. Then I would verify the servo linkage is working in both directions fully and the servo shaft is turning fully when the linkage/lever moves. The next step I would do is swap the swap the forward and reverse high pressure relief/check valves and see if the issue moves. From there you may need gauges and most likely have to pull the servo valve of from the transmission. There have been instances where the internal feedback lever has worn
Like i said i have pretty good mechanical knowledge. Checking the linking from pedal clear to the shaft coming out of the hst. All linkage is free, free from bends, clear of any obstruction and is working as it should. Tractor acts as if shaft does not spin at all which is not the case. Seems to me a check valve is stuck open and fluid is just free flowing through.
Thanks for the reply. Hoping its just a valve stuck open. Got the tractor from a golf course i live by. Previous owner said they were using it to oush up a brush pile. Pulled into the pile, backed up then it would not go forward again. So pretty instantaneous development. Hoping that a piece of debris just got knocked loose and caught in valve and wont let it shut now. Ill try swapping and see if thats the case.
Please re-read what i stated. All linkage is moving as it should. As well as the shaft coming out of the side of the hst.....it is 100 percent not a linkage issue.
Thank you for the opportunity to help you. Sorry I couldn't provide what you need. I am sure you will figure this out in no time.
Dan
Russell King
Well-known member
Lifetime Member
Equipment
L185F, Modern Ag Competitor 4’ shredder, Rhino tiller, rear dirt scoop
There has been at least one person here that had a problem where the rod through the case sheared in two, meaning the linkage was fine and turned the ”rod” that entered the case but did not move anything inside the tractor case. So hopefully that is not your problem but keep it in mind if your testing does not get you any results for improvement.
See this thread for the broken rod problem:
l3000dt - Hi-low lever broke
Hello everyone. The hi low lever broke off inside the transmission. I took the top cover off, fished out the broken pieces and ordered a new lever. The problem I'm having now, is that I cannot slide the new lever from the inside to the outside because the gear is in the way and I cannot get...
www.orangetractortalks.com
Dont thibk that is the issue because reverse works perfectly fine. I woukd thibk if the rod broke it woukd not travel either directionThere has been at least one person here that had a problem where the rod through the case sheared in two, meaning the linkage was fine and turned the ”rod” that entered the case but did not move anything inside the tractor case. So hopefully that is not your problem but keep it in mind if your testing does not get you any results for improvement.
See this thread for the broken rod problem:
l3000dt - Hi-low lever broke
Hello everyone. The hi low lever broke off inside the transmission. I took the top cover off, fished out the broken pieces and ordered a new lever. The problem I'm having now, is that I cannot slide the new lever from the inside to the outside because the gear is in the way and I cannot get...