I recenlty changed the transmission fluid and filter in my g1700 hst, replacing the fluid with 10w/30 transmssion fluid as recommended by my kubota dealer.Since then, it wont drive on start up, after about 15-20 mins it will drive but very jerky and erractically, and seems to be getting worse. Could it be the wrong oil perhaps?

Andy Briggs, September 2009

I have a L4330 Kubota with 850 hrs. I had a hyd leak on my grapple on the control block and the tractor started jerking when moving forward or reverse. I did not drive it. had it repaired and put Kubota oil back in hyd system and it is still jerking when I try to drive. The tractor lunges forward and keeps lunging until you give gas and it will smooth out. Then reverse is the same thing. Reverse seems to be worse than forward. Installed new hyd oil filter. front lift and steering does not have any problems. I have been told it was air in system and clutch disc missing disc. I don't know.... need help

Butch King, October 2019

Hi, it sounds possible that there may be air in the system as it has got worse since changing the oil and filter. Are you the same guy on youtube? Hydraulic pumps are not always self priming and may need help doing so depending on the pipework. Also there might be two pumps. A main drive pump and what is called a charge pump. The main drive and the motor work in a loop and the charge pump maintains the pressure in the system and caters for oil lost back to the tank. This is general hydrostatic info from Hydraulicsupermarket.com as i don't know the workings of the particular mower. Be careful running if it is air locked. It may whine and grumble indicating cavitation which can wear parts inside the hydraulics. Hope this helps.

Richard, June 2010

i would make sure filter is tight and not sucking air

dave, September 2009