Identify a hydraulic pump

   / Identify a hydraulic pump #1  

gdoc7112

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Aug 6, 2022
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Koiti
Can someone help me ID, make and model or at least why this pump has three hoses attached and what they are for?? This is on a piece of towed equipment we recently bought and it looks like someone replaced the pump with a 12 volt motor driven pump. It just don't seem to be working as well as it should and I wanted to attach gage but the three lines is puzzling. It should not need three...
The tags on the motor and pump are no help as they talk about type of fluid and a pressure relief
Any help would be very much appreciated.
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   / Identify a hydraulic pump #2  

WranglerX

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A Little Bit West Of Yosemite NP
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MF GC1715
Might try tracing lines to see what function they perform... Also what is "towed equipment" better description may help with identification of lines...
 
   / Identify a hydraulic pump #3  

Xfaxman

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Guthrie, OK
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Toolcat 5610 G - Bobcat V417 - TORO+Loader
This is on a piece of towed equipment we recently bought
Are the hoses powering a motor?

If so, the smaller hose is the case drain.
 
   / Identify a hydraulic pump #4  

wdchyd

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Hooksett, NH
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Kubota B2320
Looks to be a Monarch dc drive pump (Bucher Hydraulics now). The orange thermoplastic line would be your pressure output, the other with the elbow suction line, the smaller tubing line the return to tank if the built in relief valve bypasses to tank.
These units I’ve seen used for emergency aux pump drive on mobile equipment if the main engine driven pump is off or down. IE: bucket truck or crane
 
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   / Identify a hydraulic pump #5  

wdchyd

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Hooksett, NH
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Kubota B2320
Those are known for eating motor brushes if running for long periods of time, they were designed for momentary use. The suction line fittings look skimpy, the pump may be having a hard time trying to pull oil from the reservoir, thus starving the gear pump and shortening it’s life. They made different displacements but always a low flow application. A flow/load meter would show quickly it’s power and efficiency.
 
   / Identify a hydraulic pump
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gdoc7112

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Koiti
Looks to be a Monarch dc drive pump (Bucher Hydraulics now). The orange thermoplastic line would be your pressure output, the other with the elbow suction line, the smaller tubing line the return to tank if the built in relief valve bypasses to tank.
These units I’ve seen used for emergency aux pump drive on mobile equipment if the main engine driven pump is off or down. IE: bucket truck or crane
Thank you for the info. I could not figure what the smaller tubing was coming out of the pump. The smaller tubing line does go into the return. How ever this is a man lift (bucket) and has a 12 volt motor/pump as the emergency pump. the unit will work with the emergency pump but not with the pump I showed in pic's. someone messed with this and evidently replaced the main pump with this blue one but it does not do anything other than run. No hydraulic function. If you look at the last pic the black motor/pump in the background is the emergency pump. The orange hose is connected to the output side of that pump. you can see the tee at the black pump but you can't see the color of the hose but it the black one. If I was smarter I'd think there should be some type of one was check valve somewhere between the emergency pump and the main (blue) pump. If I take better pic's of how it is plumbed would you be willing to try to help me figure this out?? The unit works with the black emergency pump just not the main (blue) pump. I can't thank you enough!!
 
   / Identify a hydraulic pump
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gdoc7112

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I want to thank everyone who responded. I really needed the help.
 
   / Identify a hydraulic pump #8  

wdchyd

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Hooksett, NH
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Kubota B2320
Yes, there should check valves after both pumps to prevent back feeding thru the pump you are not using. This assuming both pumps are feeding a separate set of control valves.
 
 
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