Backhoe attachment

[Vigo327]

Don't I lose my loader function by doing that ?

No.

The PB port is an outlet from your loader valve, not an inlet. The loader will function exactly as it already does. The only caveat to feeding the backhoe from your loader PB port is that pulling a loader valve will cut power to the backhoe, which is a total non-issue because you never HAVE to use both simultaneuously.

If you think about where that hose starts at your loader PB port, and ends at your hydraulic block, you are basically inserting your backhoe valve between those two points.

 

[rScotty]

Well here it is. Picked it up today. He claims no top link used with this sub frame and he didn't have one hooked up ?

It looks nice. Next step would be to make the sub frame fit.
You might want to contact Woods to conirm the top link. That subframe looks very strong, but without a top link it needs to fit the tractor very well. I don't see a downside to a top link.

rScotty

 

[rScotty]

No.

The PB port is an outlet from your loader valve, not an inlet. The loader will function exactly as it already does. The only caveat to feeding the backhoe from your loader PB port is that pulling a loader valve will cut power to the backhoe, which is a total non-issue because you never HAVE to use both simultaneuously.

If you think about where that hose starts at your loader PB port, and ends at your hydraulic block, you are basically inserting your backhoe valve between those two points.

Don't you think that plumbing the system that way also depends on having a PB port on the backhoe valve stack? I think it needs a path to take the high pressure flow from the backhoe back to the hydraulic block.
rScotty

 

[Vigo327]

So this is an assumption..but MOST backhoe valves are sectional valves where you can stack up more valve sections. On a monoblock unless you can find documentation that says so you have to wonder if the ‘return’ or tank port passages can handle full line pressure without cracking the housing. But my ASSUMPTION is that on a sectional type valve set, for SURE all the galleys in the valve sections are designed to hold full pressure and the only part that MIGHT not be rated to that pressure is the outlet housing, but i suspect it would be fine in nearly all cases.

So even though it is not always a good idea to subject a valve set’s tank port/passages to high pressure, im suspecting that on a backhoe sectional valve set that usually is fine.

I replumbed a backhoe on a small kubota tractor to work this way and it has been fine so far. I put a gauge on it and im subjecting the backhoe valve outlet to ~1400psi, no problems yet.

 

[rScotty]

Best of all would be if we could find both a PB and a return port on the sectional valve - and it might have that configuration already - or be available. Sectional valves tend to have every option.
It would help if we had a fluid schematic for the Woods sectional valve. Woods might be able to help out on that & someone ought to ask. They have probably seen every configuration there is.

 

[John1550]

Best of all would be if we could find both a PB and a return port on the sectional valve - and it might have that configuration already - or be available. Sectional valves tend to have every option.
It would help if we had a fluid schematic for the Woods sectional valve. Woods might be able to help out on that & someone ought to ask. They have probably seen every configuration there is.

Does this help

 

[Vigo327]

So the way i recommended plumbing it would technically put pressure on the outlet port of the backhoe IF you put the 3pt under pressure somehow. But if you didnt, or if the tractor has position control i dont think you even could (because it would just hit the target and stop pushing?), it is simply routing the backhoe exhaust flow through the 3pt plumbing before returning to tank, just as that flow currently does now. I recommended to do it this way because it is the simplest in terms of making or moving connections. Just ‘put the backhoe valve in series between the loader and 3pt on the power beyond line’.

 

[John1550]

So the way i recommended plumbing it would technically put pressure on the outlet port of the backhoe IF you put the 3pt under pressure somehow. But if you didnt, or if the tractor has position control i dont think you even could (because it would just hit the target and stop pushing?), it is simply routing the backhoe exhaust flow through the 3pt plumbing before returning to tank, just as that flow currently does now. I recommended to do it this way because it is the simplest in terms of making or moving connections. Just ‘put the backhoe valve in series between the loader and 3pt on the power beyond line’.

Huh ? Lol

 

[Vigo327]

Dont worry, I didn’t know much about hydraulics a year ago either but ‘look at me now’

 

[John1550]

Dont worry, I didn’t know much about hydraulics a year ago either but ‘look at me now’

Maybe a sketch would help