farmerscottuk
New member
Hi,
I've just discovered this is anything it is a wealth of knowledge and I'm hoping for some help.
I've got an X900 and when you're pulling away the best way to describe her is "jerky" or "hesitant" on the hydrostatic transmission. You give her some gentle revs and she goes to pull away and then stops and then goes and so on. Almost like the pressure fluctuates. If you keep her at a slow speed of say 2 mph you can feel her serging. If you put you foot down quickly she will pull away as normal and quickly gets up to 22mph (she's always had this top speed from new) but you can still feel some hesitation or surging as she is accelerating. We have owned her from new (2015) and she has been fully serviced by us every year.
I've covered the basics (I think) as follows:
Engine is running well and revs freely in neutral as well as under load.
She move freely in neutral and all wheels move freely by hand.
Both filters changed.
Tank strainer cleaned. (nothing much on it)
Hydraulic oil replaced. (super udt and old oil looked clean and is changed every year)
Dump valve is free moving and fully out and carriage is adjusted with 1mm gap.
All hoses seem fine with no collapsing and no leaks.
I've checked the charge pressure which is 85 psi on tick over rising to 95 psi when revs increased (havent checked to precise rpm based in wsm) but the gauge clearly fluctuates up and down.
Obviously the fluctuations on the gauge are my biggest worry and this corresponds with the hesitations/surging that I'm getting when moving but before I open up the transmission I'm wondering if there is anything simple I'm missing? It almost seems like a valve is letting past but that is probably wishful thinking. I haven't checked any other pressures as I'm waiting for a set of high pressure gauges to be delivered.
Sorry for the long winded post but any help would be much appreciated.
I've just discovered this is anything it is a wealth of knowledge and I'm hoping for some help.
I've got an X900 and when you're pulling away the best way to describe her is "jerky" or "hesitant" on the hydrostatic transmission. You give her some gentle revs and she goes to pull away and then stops and then goes and so on. Almost like the pressure fluctuates. If you keep her at a slow speed of say 2 mph you can feel her serging. If you put you foot down quickly she will pull away as normal and quickly gets up to 22mph (she's always had this top speed from new) but you can still feel some hesitation or surging as she is accelerating. We have owned her from new (2015) and she has been fully serviced by us every year.
I've covered the basics (I think) as follows:
Engine is running well and revs freely in neutral as well as under load.
She move freely in neutral and all wheels move freely by hand.
Both filters changed.
Tank strainer cleaned. (nothing much on it)
Hydraulic oil replaced. (super udt and old oil looked clean and is changed every year)
Dump valve is free moving and fully out and carriage is adjusted with 1mm gap.
All hoses seem fine with no collapsing and no leaks.
I've checked the charge pressure which is 85 psi on tick over rising to 95 psi when revs increased (havent checked to precise rpm based in wsm) but the gauge clearly fluctuates up and down.
Obviously the fluctuations on the gauge are my biggest worry and this corresponds with the hesitations/surging that I'm getting when moving but before I open up the transmission I'm wondering if there is anything simple I'm missing? It almost seems like a valve is letting past but that is probably wishful thinking. I haven't checked any other pressures as I'm waiting for a set of high pressure gauges to be delivered.
Sorry for the long winded post but any help would be much appreciated.