Kubota will not go forward after it runs a while

[Bobbybrushhog]

Would anyone know why when running my kubota L4240 hydrostatic tractor for a while, when going in reverse, it kinda jumps forward before going into reverse, then, it will not go forward?

 

[murphy1244]

How many hours and did you do anything before this started to happen?

 

[Bobbybrushhog]

Thanks for responding murph. I have over 1800 hrs. This only happens when the tractor warms up. I mow a lot of rough stuff.

 

[Tx Jim]

How long since hyd filter was changed? I presume the hyd oil is at the full mark.

 

[CJONE]

Thanks for responding murph. I have over 1800 hrs. This only happens when the tractor warms up. I mow a lot of rough stuff.

Usually when a hydrostat warms up then looses charge pressure you have worn units, both pump and motor. But severly degraded fluid will cause the same problem but that usually means damage to the pump/motor. A plugged filter will cause problems when cold usually but fluid/filters is a good place to start along with charge pressure. Worn charge pump reliefs will cause this problem also. CJ