Currently working on some hydraulic issues with the M125X tractor and have questions regarding hydraulic filters. The tractor has three spin on elements. Two suction, one for each pump, and another one on the lift housing. The parts book lists it as a hydrostat (or maybe it was HST)filter element. I'm curious as to what this element does. Where it's mounted it doesn't seem likely that it's associated with the transmission system functions. It's available OEM and from other replacement suppliers, all in the $40 range, so it's probably not a high pressure item. Is it simply a return type filter for exhaust fluid from the lift system?
M125X Hydraulic question
- Thread starter Fedup
- Start date
The "HST" filter in the power shift "M" tractors filters the oil that operates the powershift. It is a finer (higher micron) filter than the two hydraulic filters on the bottom. It filters the oil before it goes to the power shift so it has to withstand the 290 to 330 psi that the pressure regulator sends to it and that ultimately goes through all the little valves and ports in the power shift controls. Do not scrimp on this filter! You would be better to not change it at all than put an inferior filter on here.
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My philosophy about filters (and remember I own 2 M Series ag tractors is... Always use genuine Kubota filters and change them out (as well as fluids) on the correct change intervals.
Every filter on both my machines are Kubota including the inner and outer air filters.
The price difference between Kubota filters and the 'others' is really inconsequential.
Every filter on both my machines are Kubota including the inner and outer air filters.
The price difference between Kubota filters and the 'others' is really inconsequential.
We ARE discussing the single spin on filter mounted on the left side of the three point lift housing, right? What I see in the parts diagram shows the output from right side hydraulic pump (I assume that's the transmission/steering pump) leading to the pressure regulator. You're saying the oil flows from there back to the lift housing and through this filter before going to the power shift valve?
I'm not trying to scrimp on the price of a filter here, just trying to get a handle on what the filter is/does and how it fits into the system.
I'm not trying to scrimp on the price of a filter here, just trying to get a handle on what the filter is/does and how it fits into the system.
Yes, the oil flow from the power steering pump is split by the pressure regulator valve and flows back to the spin-on filter on the left side of the tph housing and the power shift control valves. The rest of the oil flows to the power steering.
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Warning!!! I may have misled you! I have always believed what I wrote above but looking at the circuit diagram in the WSM it looks like you are right and that filter actually is a return filter for the TPH! Sorry, And my face IS quite red!!
I appreciate the update. Thank you for that. While I had no reason to doubt your earlier statements concerning the filter in question, considering where it's located I did find it hard to see it as part of the transmission circuit. What's shown in the diagram you posted makes sense. Other tractor makers do use a high pressure filter in powershift circuits the way you described, but most of them are larger than this one, made from heavier material, and usually run in the $80, $90, and up price range. They usually come with a separate base and are mounted on a bracket somewhere. This one just didn't look like it fit that bill.
When I first looked at the tractor yesterday, it was a cold and windy day, the tractor was dirty and the yard pretty muddy so I didn't spend a lot of time crawling around under it, so I couldn't really tell a great deal about the pumps and the layout.
Thanks again for your help. Having that diagram to study is a great help.
When I first looked at the tractor yesterday, it was a cold and windy day, the tractor was dirty and the yard pretty muddy so I didn't spend a lot of time crawling around under it, so I couldn't really tell a great deal about the pumps and the layout.
Thanks again for your help. Having that diagram to study is a great help.