Hydraulic pump question

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I am replacing the hydraulics on an old Economy Power King tractor and hope someone out there can help. I have a pump from a Toro triplex fairway cutter. The information on the tag is: Webster Electric Company Inc. OH5BS   OH5B    OH5B-RB   8211   B76. As you can see in the pic it has the 2 connections on the "top" and three on the bottom. Could I just plug the bottom 3 ?  Which of the top is in and which is out? I have some theory but hope to find someone with more knowledge. I also included a pic of the valve. I know I will also have to include a tank in the system since the original was self-contained with the pump. Any help or direction about any of this conversion would be greatly appreciated. Thanks RON Attached Images
Reply:Hey Ronbo,That looks like a three section pump, or possibly a two section pump with an integral flow control. Any valves or fittings visible in the rear section?The two lines are most likely "in" or suction.No, you probably can't plug anything, but you probably could combine the pump outputs into one work line.The valve looks like a simple open-center control. Most likely: In - pressure from pump,  Out -return to tank, Up and  Down.Hopefully you could run the Webster numbers for positive ID.Good Luck
Reply:I wonder if you could remove one of the center sections.My father was a 1974 econamy with dual trannies.My homemade front end loader is biult on an old economy frame and rearend.The transmissions used are really Crosley car trannys. Kinda neat.Tim Beeker.
Reply:I think Denrep  is right or damn close :-).The only thing I'd add is that the two inlets appear to be #12 ORB to #12 JIC 90deg fittings, (size could be off hard to tell from here).I'd say the two hoses on the bottom close to the center/top of the pic are the outlets and the one on the bottom/end could be a case drain.By the size of the sections I'd guess  4-6 GPM. Pumps with multiple sections usually  can have the extra section removed and the remainder fit back together if you only want one section.I'd also guess that it it doesn't run at much pressure being a belt drive with two sections, either that or the GPM is way lower than I thought.....Mike
Reply:I would be suprised if it has a case drain, I see those on piston pumps, haven't seen a case drain on a vane or gear pump.  Could be wrong.I agree about the fitting type/size ( hard to tell without something in the pic to gauge size with).Just for FYI the dash sizes or based on one inch being 16, so a -8 is a half inch, -16 is one inch, -20 is inch and a fourth......etc.The o-ring boss (ORB) fittings are also dash sizes, so a -16 fitting takes a -916 o-ring, -20 a -920 o-ring.Just trying to help.Last edited by tnjind; 08-09-2008 at 01:49 PM.Reason: speeling, as alwaysTim Beeker.
Reply:+1 to Denrep.It should not be difficult to disassemble and take a look (unsrew rear bolts). Also can play with jar of oil  - and turn by hands - will give an idea about which suction works on which outlet...My feeling is that depending on combination suction/oulet can yield much more than 6gpm... If let say both suctions work on all outlets it would work out as 1/2" tube in/out.- that is well over 10gpm From other hand second angle can be relief... Have to take a look...
Reply:This is starting to sound like it may start costing money for fittings. Really trying to keep cost to a minimum. I took the pump apart and there is no way to (easily) eliminate one or two of the outlets. It does look like two separate pumps inside but the driven shaft extends the whole lenth. I dug around and found another one from a Toro Sand pro bunker machine and I think it will work. It's about half the size and has one inlet and one outlet. See pics.Thanks for your input. RON Attached Images
Reply:Sorry wrong pis. Those are the valve. This is the pump. Attached Images
Reply:Probably a better choice. That's a simple open center gear pump -except for two tricky cross bolts near the flange.Any idea of original pump specs? What does it power? Could you live with slower hydraulics?With that belt arrangement it should be fairly simple to retrofit to another pump, even if pulley size needs to be changed.What needs to be first determined is pump flow rate at working rpm. It could be calculated by measuring the pump cavity, pulleys, etc, but probably a run test would be just as easy. See how much fluid it pumps into a bucket in 15 seconds, at run speed,  multiply by four (= 60 seconds) to estimate pump GPM.Good Luck
Reply:I don't know any of the specs on this pump. The only thing it will run on the tractor will be a relatively small hydraulic cylinder about 2" bore with an 8" stroke. The pump came off a three wheel machine with 2 cylinders about the same size and all three wheels were driven by hydraulic motors, all driven by this pump. I am assuming the volume output would have to be pretty high to handle that. I don't need this to operate things too fast. I am guessing I could slow down pump speed by pulley size, reducing flow. Right? RON
Reply:Originally Posted by ronbo...The only thing it will run on the tractor will be a relatively small hydraulic cylinder about 2" bore with an 8" stroke.... The pump came off a three wheel machine with 2 cylinders about the same size and all three wheels were driven by hydraulic motors, all driven by this pump...
Reply:It's possible there was another pump for the drive wheels on the original use. It's been quite a while since I tore this one apart. I got ahold of several old machines from a golf course I work part time as a mechanic and salvage everything I think may be usable. I've gathered quite a pile of stuff to dig through. I was thinking of using one of the hydraulic drive motors for a rear PTO on the tractor but I don't think I could get enough speed (RPM).
Reply:You can't plug them.  Many hydraulic systems will have multiple pumps of varying sizes to control the power and speed of multiple systems.  If you want to remove a pump from service do not plug it, simply run its discharge line back to the hydraulic tank.  A plugged hydraulic line will cause the system to overpressurize instantly and do massive damage (seen it first hand).You could also parallel all of the pumps together but the system relief has to be large enough to handle the volume.   Your equipment will operate very quicly. This also tends to generate a lot of heat and if you have a small reservoir that could represent a problem.