Zero turn hydrostatic jerking problem
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Zero turn hydrostatic jerking problem
I have a 3 year old Sears Craftsman Z7100 Hydrostatic drive, zero turn mower. My issue is that the hydrostatic drive has become jerky which is most notable when driving slowly and particularly in a left turn. It is not noticeable when the maching picks up speed. The manual doesn't address this issue or servicing of the system. Is there something that I can do to reduce or eliminate the jerking in the drive?
#3
Jerky as in overly responsive to movement of the controls? That would almost make me wonder if the right side was actually getting weaker, making the left side seem more responsive in comparison.
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No, the right side operates much closer to normal. The symptom is more like you can't go smoothly from a stop to a slow forward movement. It's like a lurching which makes it hard to maneuver tight areas. Once it gets going, it's fine. More of a repetative hesitation then going type of thing.
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Some time the levers and linkages that connect the control arms to the hydro pump can get loose and have play that can affect the way the unit operates. I would suggest checking everything to make sure it's all tight and there is nothing loose.
In addition to this on many Z's the control arms have dampeners on the controls, these are kind of like small shock absorbers that help slow down and smooth out the speed at which you can move the control arms. If the dampeners loose their oil they get loose and no longer allow for smooth operation of the controls, if this happens they need to be replaced.
In addition to this on many Z's the control arms have dampeners on the controls, these are kind of like small shock absorbers that help slow down and smooth out the speed at which you can move the control arms. If the dampeners loose their oil they get loose and no longer allow for smooth operation of the controls, if this happens they need to be replaced.
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Alex777aw,
I'm having the same issue, and you seem to describe it best...jerking at low speeds / turning and stops after speeding up. Am I understanding that the drive is still working after experiencing this problem 4 years ago? I'm debating on whether or not to replace the drive/pump assembly ($650
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Thanks!
I'm having the same issue, and you seem to describe it best...jerking at low speeds / turning and stops after speeding up. Am I understanding that the drive is still working after experiencing this problem 4 years ago? I'm debating on whether or not to replace the drive/pump assembly ($650

Thanks!
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I gave the machine to my son, but I'm sure that the problem still exists. It would only do the jerking hesitation thing in a slow turn or upon initial acceleration. Once it gets going it's fine. It doesn't go and stop, it just has the jerking.
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It was surprising news to them. Never heard of such a thing. They have no maintenance at this location so it would get sent out to somewhere else. Just a bunch of know-nothings working at this store. I like Sears tools but never cared much for their mowers and other things that they don't even build and whose parts numbers are Sears specific and you have a hard time finding them elsewhere.