Lil Foot
Well-known member
Lifetime Member
Equipment
1979 B7100DT Gear, Nissan Hanix N150-2 Excavator
When I rebuilt the multiple spool valve on my B670, it was fully functional, just leaky. It was caked with dirt & old oil, so I pressure washed the outside, and began disassemble it immediately in case I had gotten any water inside. I disassembled each valve individually, removing o-rings & cleaning the parts with brake cleaner, brass & stainless brushes, & compressed air, then bagging the parts separately to keep from mixing the parts between valves. There was a little rust in a few spots & I used scotchbrite, fine emery, and crocus cloth to clean it up. Always sand/polish 90 degrees to the direction you want to seal.
(for example, do not sand/polish along the long axis of a spool, only radially around it, and remove the absolute minimum of material) Don't want to provide any new micro leak paths, you will already have plenty just from age/wear.
I bought the o-rings from an industrial supply house, in this case the local Parker store, (Parker o-rings) but any decent seal supply house should be able to sell you what you need. I don't have the exact quantity of each size written down, but the receipt lists a total of 49, with extras in case I dropped/damaged any during the process. The individual sizes are listed in my notes as:
sm valve body 2-012 qty 28
lg valve body 2-013 qty 7
sm spool 2-012 qty 7
lg spool 2-112 qty 7
All o-rings, grooves, & hard parts were wetted with hydraulic oil at re-assembly.
The mylar shims are something of a mystery, mine only had one intact & two partials at disassembly, and my hydraulics expert said the only reason he could see to have them in the valve was to keep the individual valve bodies from rusting together. No one at Kubota had a clue what I was even talking about, nor did two local hydraulic shops. My control was put back together with no mylar shims and seems to work fine.
If I'm really careful, I can get two functions at the same time with mine, but it takes careful feathering- I just don't think the pump puts out the volume to do that effectively. If I feel the need for two functions, I find it easier to quickly alternate the two movements back & forth, seems easier/quicker to me.
Hope this long-winded dissertation helps.
And I made a mistake- the cost for the o-rings was $6.56.
(for example, do not sand/polish along the long axis of a spool, only radially around it, and remove the absolute minimum of material) Don't want to provide any new micro leak paths, you will already have plenty just from age/wear.
I bought the o-rings from an industrial supply house, in this case the local Parker store, (Parker o-rings) but any decent seal supply house should be able to sell you what you need. I don't have the exact quantity of each size written down, but the receipt lists a total of 49, with extras in case I dropped/damaged any during the process. The individual sizes are listed in my notes as:
sm valve body 2-012 qty 28
lg valve body 2-013 qty 7
sm spool 2-012 qty 7
lg spool 2-112 qty 7
All o-rings, grooves, & hard parts were wetted with hydraulic oil at re-assembly.
The mylar shims are something of a mystery, mine only had one intact & two partials at disassembly, and my hydraulics expert said the only reason he could see to have them in the valve was to keep the individual valve bodies from rusting together. No one at Kubota had a clue what I was even talking about, nor did two local hydraulic shops. My control was put back together with no mylar shims and seems to work fine.
If I'm really careful, I can get two functions at the same time with mine, but it takes careful feathering- I just don't think the pump puts out the volume to do that effectively. If I feel the need for two functions, I find it easier to quickly alternate the two movements back & forth, seems easier/quicker to me.
Hope this long-winded dissertation helps.
And I made a mistake- the cost for the o-rings was $6.56.
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