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Boom Lift salvage yard

TVA

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F3E20245-1312-4998-B84C-8FF5B20E45BC.jpeg The red arrows is check valves, the green arrow is shuttle!
 

TVA

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Yes TVA, the local hydraulic shop I took the block to said the same thing and I watched the technician remove both of the shuttle valves and look at the little spring and steel balls and the seat inside the block ( picture posted earlier in this thread) and he could see no visible damage, and he also took some measurements with a micrometer inside the shuttle area of the block, and said he could see no damage, but would recommend replacement of those shuttles, and he looked for some part numbers on the shuttle cap head and sides, but could find no numbers.

So I am curious, if I remove the shuttle cap and springs, and physically hold the balls on their seat with my fingers or a stiffer spring or something, should that keep the air from passing between the two large beefy Inlet ports to the hydraulic brake block? Maybe I could spend the balls around and see if that provides a better seal? Or install stiffer Springs to hold the balls more tightly to the seat?
The shuttles and checks operate on pressure difference between two ports, the spring inside checks is for assistance when pressure is low on start up. The ball type shuttles don’t have springs in them because springs will interfere with ball sealing on its seat, the spool type may or may not have weak springs in them!
 

Ronray

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View attachment 201885 Shuttle valve for shift cylinder and park break release would be the first suspect for cross port leakage.
View attachment 201885 Shuttle valve for shift cylinder and park break release would be the first suspect for cross port leakage.

On the picture red arrow either shuttle valve or check valve for counterbalance marked with yellow arrow.

Thanks TVA. I'm going to disassemble the shuttle cartridge you have pictured with the yellow arrow, and I will get a picture of all of the components at both ends and Post-it a little later for you to see to hopefully help clarify my understanding.
 

TVA

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Thanks TVA. I'm going to disassemble the shuttle cartridge you have pictured with the yellow arrow, and I will get a picture of all of the components at both ends and Post-it a little later for you to see to hopefully help clarify my understanding.
By the yellow arrow I marked the counterbalance valve, not the shuttle valve, my post said: with red arrow I marked shuttle valve, OR!!! - check valve associated WITH!!! Counterbalance valve marked by yellow arrow! Because I don’t have pictures or illustrations, of all of the six sides of the block and it’s innards - I cant know for sure! But by the looks of it and proximity to components, I made two assumptions!
 

TVA

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The red circle - counterbalance valve

The blue arrow - adjustment screw you can see on on picture

The yellow circle - the check valve associated with red circle counterbalance valve.

Now you would have to look for shuttle valve, with connections I started in post above.
 

Ronray

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The red circle - counterbalance valve

The blue arrow - adjustment screw you can see on on picture

The yellow circle - the check valve associated with red circle counterbalance valve.

Now you would have to look for shuttle valve, with connections I started in post above.

I don't see a picture with red and yellow circles?
 

Ronray

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By the yellow arrow I marked the counterbalance valve, not the shuttle valve, my post said: with red arrow I marked shuttle valve, OR!!! - check valve associated WITH!!! Counterbalance valve marked by yellow arrow! Because I don’t have pictures or illustrations, of all of the six sides of the block and it’s innards - I cant know for sure! But by the looks of it and proximity to components, I made two assumptions!

Okay so I am going to post some pictures of the inside of the counterbalance valve as well as pictures of all six sides of the valve block, so give me about 10 or 15 minutes to do that since I can only post three pictures at a time.

Also I made a big discovery yesterday when I took the valve block back apart. Apparently there is supposed to be cross port leakage between the two beefy in coming forward and reverse hydraulic lines to the valve block. I removed some of the allen screw plugs and saw that there was a hole drilled connecting those two Inlet ports. And the hole was about I would say 1/16 of an inch or 1/8 of an inch in diameter.
 

Ronray

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20190915_191922.jpg 20190915_205900.jpg 20190915_205922.jpg 20190915_205955.jpg Parts in order from inside of dynamic brake counterbalance valve shaft.

Not sure if I have the sleeve over the piston backwards or forwards, but I think it should be with the rubber o-ring towards the outside, the right side of the picture?
 

TVA

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TVA

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0CFE321D-1DC3-4B49-A5D6-D3BA5B5AB306.jpeg Is this just a plug, or there’s small spool behind it?
 

Ronray

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View attachment 201957 Is this just a plug, or there’s small spool behind it?
Just a plug, with no spool behind it. With this plug removed I was able to see the small drilled hole connecting the two Inlet ports. And I shined a light and stuck a paperclip through the tiny small drilled hole to confirm it was unobstructed.
 

TVA

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Show me under what plug those parts that in the three last pictures.
 
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