I just picked up a BL4590A backhoe but the pto pump is missing. I know I can get one at Kubota but they are pricey. I see aftermarket ones out there but which one is better than the other and how many gpm would I need ?
Pto pump for backhoe
- Thread starter blueshadow
- Start date
Depends on the hoe, more specifically the size of your cylinders. The correct way to do it would be to calculate your largest cylinder's displacement and then how fast you want\need it to move. That'll give you a gallon's per minute figure. Add 15% to that to account for restrictions and that's about the size pump you need.
However your valves will only flow a certain amount, excess fluid is dumped back into the reservoir. Most will have a recommended minimum HP. Get something equal or less than your machine and you'll be fine.
I'd give these guys a call and explain what you're doing and I'm sure they'll hook you up. FYI you'll need a relief valve and reservoir tank unless the hoe has those, also check the input\output fitting sizes on the hoe.
However your valves will only flow a certain amount, excess fluid is dumped back into the reservoir. Most will have a recommended minimum HP. Get something equal or less than your machine and you'll be fine.
I'd give these guys a call and explain what you're doing and I'm sure they'll hook you up. FYI you'll need a relief valve and reservoir tank unless the hoe has those, also check the input\output fitting sizes on the hoe.
Matt,would calculating just one cylinder plus 15% give enough flow to operate more than one cylinder at once? when I'm operating a backhoe I can be moving,or trying to move if the flow rate will allow,up to 4 rams at once.
Dave
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I have BL 4520 backhoe. I don't know how similar it is sized to yours. Mine is supposedly 6-1/2'. Anyway, I have a Woods manual for the equivalent model 650/750 and it specifies that the pto pump is 2.1 cubic inches, which at 540 rpm is approximately 4.9gpm.