school me on adding another hydraulic circuit

motionclone

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L345DT with Lp mower, forks and grapple thumb, Bobcat 337 Midi Ex
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I want to add a grapple to my forks and thats going to require a way to power the cylinder on the grapple.

I have a L345dt with a great bend loader. The loader is powered by tractor hydraulics attached to the block under left side of the seat.

Where/ how to tap into tractor hydraulics and is it possible to use a NOS fisher plow valve to actuate the cylinder. I have a couple new never used valve bodies sitting on a shelf.
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
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What size fittings are on the fisher valve, I'm betting 1/4", which will restrict flow on the tractors hydraulic circuit.
Another issue is are they Open center valves?
And it's placement in the system would depend on if the loader valve has a relief valve or if the fisher valve has a relief valve.

If you lucky enough for them to be 3/8 or larger and for it to be open center and for it to have a pressure relief valve then it will work.

Part# for the fisher valve?

This very scenario is why 3rd function valves are pricey!
 

motionclone

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L345DT with Lp mower, forks and grapple thumb, Bobcat 337 Midi Ex
May 4, 2018
1,398
992
113
Maine
OK, Not sure how to tell live center by looking so maybe the casting will give it away?

Looked up only serial number on it and came up with nothing.
Tape measure pics are at IN port and what I assume is out port (smaller)








 

motionclone

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Equipment
L345DT with Lp mower, forks and grapple thumb, Bobcat 337 Midi Ex
May 4, 2018
1,398
992
113
Maine
If that valve body isnt usable whats this option on a electric diverter valve on the curl cylinder? Probably wouldnt need curl and thumb at same time right?

Or would be better to get a single spool valve and tie into hydraulics somewhere
 

North Idaho Wolfman

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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
28,306
4,856
113
Sandpoint, ID
I will say everything looks like it will work, that's actually a loader valve style, it's a little overkill for just a grapple, but it should work.
flow should be fine with it.
You could pipe it in before the loader valve or after.

Blow air (like with your mouth) in the in port and if it freely blows out the out port then your good to go if it doesn't then it's set up as a closed center valve.\

Being that it has a pressure relief valve on it it, normally it should have 3 lines there should be In, PB and tank ports, but that's not 100% true all the time.

Also the odd layout of the valve ports has me wondering if it's not a common type of valve configuration???