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Hough h80b steering priority valve

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Hi all,  

I have a hough h80b with a modified  priority valve circuit  which isnt suited for the task  (valve generates excessive heat and boom raise speed slow at 18sec @2500rpm) the valve in question is plumbed off the steering pump which  has two outlets , one of which goes directly to the steering control valve while the other outlet passes thru the priority  valve and splits into two, one line of which then connects back into the original output line from pump to scv while the other joins into the hydraulic function control valve supply line .the steering pump is a commercial p350  which i assume is original and unmolested which my operators manual states is a dual element fixed displacement gear pump with rated max flow of 42gpm and charging flow of 21.8gpm now my problem is i wish to replace this old modified priority valve with something like a parker adjustable  priorityvalve withthe apropriate flow rate but am  unsure as to weather the valve curcuit i have now was plumbed correctly to begin with ,ie which outlet from steering pump flows what rate and which one should be prioritised to steering as the flowrate at 42gpm seems  very high any input  would be greatly appreciated 


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Thanks for that , i can see straight away that the steering pump on my machine is not the same as in the parts book🙁 as the outlets are arranged vertically  from the same  pump section with an seperate priority valve. I also think it has been plumbed  incorrectly  as one outlet from my pump bypasses the controlled flow through the priority valve which to my way of thinking defeats the purpose  of controlling  the flow in the first place as well as throttling  flow through to your hydraulic function circuit however  im not really sure as to how the pumps and priority / diversion valve worked together in the original  system, I think ot should be more like in my second pic


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