.... Back to my question. Does it seem reasonable to interrupt the pressure line to FEL valve, install a hydraulic manifold , then take outputs from the manifold to the FEL valve and to the the log splitter (or whatever is plugged into that output)? ....
In part the answer to that question depends on
your answer to a previous question:
How many lines does your current FEL control valve have?
From looking at Branson parts, loader and tractor manuals I found on a
Branson Dealer website in Austrailia I'm almost certain you will find you have:
4 each - hoses to the FEL cylinders ('working ports')
1 each - pressure feed from tractor to the FEL valve ('P' port)
1 each - power beyond back to the tractor ('PB' port)
1 each - relief flow back to the tractor tank (the right side of transmission case) ('T' port)
TOTAL -
7 lines connected to your FEL control valve
IF that is correct, you have a constant-flow hydraulic system and your FEL control valve is the open/tandem-center type and already has Power Beyond capability.
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IF that is correct and you insist on the 'manifold approach' then the manifold
s (yes, multiple manifolds, keep reading)
must be a selector-type where you select which control valve is in-use (one at a time only) and it must incorporate a relief valve with return to the tractors tank as described by oldnslo in his post above.
Why all of that? Because:
1. If you install an 'open' manifold where fluid can flow to either control valve all the time, then the fluid will always flow to the 'other' valve when you try to operate one, passing freely through the 'other valve' open center. No working port will get anything near operating pressure.
2. If you install a selector-type manifold (use either/or control valve but not both simultaneously) to avoid problem 1, then you can easily 'deadhead' your tractor pump during switchover which will cause instant over-pressure and destruction of the 'something' that has to 'give' when that happens (pump casing, pump drive coupler, a pressure pipe .... whatever is the weakest link and it won't be good, may be dangerous to the operator, will be expensive to fix).
3. Problem 2 can only be avoided by the added complexity of a manifold pressure relief valve and return hose to the tractor tank - that's the 'bypass' to avoid damaging deadhead during switchover of the manifold selector.
Why multiple manifolds? Because:
4. You have to address not only the 'P' pressure feed to each control valve, you also have to address the 'PB' pressure feed back to the tractor for each of those separate control valves. There's also the multiple low-pressure 'T' returns to tank/transmission that'll have to be addressed, but those can be an 'open' junction.
^^That's all a
very complex approach, fraught with risk if the switchover of both 'P' and 'PB' isn't coordinated, a PITA to juggle all the manual switchover stuff, that's why ....
.... I have not heard of this solution before ....
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IMHO the "proper" and "safe" solution, the KISS solution intended and traditionally used for a system design like yours (and
many other CUT's) for good reason:
- Install correct open/tandem center control valves with 'PB' and 'T' ports/hoses (which is what your FEL control valve already is) in series for any/all aux implement controls.
- In order to ensure delivery of the full ~8.x GPM that your tractor pump is capable of, all of the 'P' and 'PB' lines and fitting in that series-path should be 1/2" (#8) as previously stated by Brian (even if the implement itself uses a smaller hose/fitting at the working port connection).
Note that all of these same control valve-type and hose/fitting size rules apply even with the 'manifold approach'.
The "proper" solution is fully passive - you can use whatever external implement at-will with no manual switching of anything and it serves for lot's more other common and convenient rear-aux implements than just a static log-splitter (e.g. bucket grapple, hyd top link, etc, the list is endless when you have a rear aux that's 'conventional').
So why would one choose the 'manifold approach' which does
nothing but add parts (
more cost), complexity and the inconvenience of 'only-one-or-the-other-selection' when compared to the 'traditional' solution?