Using a power steering pump for hydraulics

[john_bud]

Can you use one? Absolutely! They put out much more than 2 gpm that was listed. Well, to be accurate, many put out more. Some may only put out 2. I think most put out about 5-7 gpm at 800-1400 psi. But that's from my notoriously poor memory... The majority of ps systems ARE open center. The fluid just flows out and back at low pressure until the valve directs it agains a cylinder where it builds pressure and moves the cylinder. Only at the stops, it is against the relief. That's why when you hold the steering wheel all the way over it sounds different. It is also a bad thing to do as it heats the fluid up going across the relief. I would get some junk yard PS cooling loops and use them to help cool the fluid and add a large reservor for the fluid

A buddy had a $100 ford bronco with a rusted out body with a good 200cid straight six, a decent 4x4 driveline and most of a free jeep body, so he striped the bronco and put on the jeep front end and cobbled a cab up. In the back he used a 265gal oil barrel (also free) cut in half the long way to make a dump bed. He machined a 3" single acting cylinder out of pipe on his lathe for under 20 bucks and powered it from a PS pump. It would lift and dump a full load of oak or dirt with no problem at all and the engine at idle. It also powers a home made snow plow on the front. I did some minor help on the project and donated older tires for it. I think he had under $400 in the whole project.

By the way, he called it a "Beep" for half Bronco half Jeep.

jb

 

[GT2]

The majority of ps systems ARE open center. The fluid just flows out and back at low pressure until the valve directs it agains a cylinder where it builds pressure and moves the cylinder. Only at the stops, it is against the relief. That's why when you hold the steering wheel all the way over it sounds different. It is also a bad thing to do as it heats the fluid up going across the relief. I would get some junk yard PS cooling loops and use them to help cool the fluid and add a large reservor for the fluid
jb

Ok, finally something that makes sense!!!

I was wondering how you would cool the fluid if it were by-passing all the time.

I'm starting to think it would be better to use two pumps, one for steering and one for acc's.
Thanks, Tim

 

[RickB]

Ok, finally something that makes sense!!!


I'm starting to think it would be better to use two pumps, one for steering and one for acc's.
Thanks, Tim

That's going to be simpler and safer than trying to split the flow from one open center pump.

 

[john_bud]

Yep, 2 pumps are better than one as they say. Uh, I'm not sure exactly who says that... but it's still true!

Typically, bigger vehicles have bigger PS pumps that flow more volume and at a higher pressure. It may make the bracket fab easier too if you remove the on pump reservoir and use a remote tank. They are pretty easy to weld up.



jb

 

[nik12]

Yes, you can use a power steering pump to run small cylinders, but you must treat it as a separate hydraulic source and not simply tee into the existing steering circuit, especially if it is an open‑center steering system.

Typical automotive power steering pumps only supply a few GPM at moderate pressure, so they will move a single plow or 3‑point cylinder slowly but can be acceptable if you do not need high speed or big lifting force. The unsafe part is teeing into a tractor’s steering line: an open‑center steering circuit needs uninterrupted flow and often priority over everything else, so sharing that line without a proper priority valve can make steering lag or fail when you lift, which is a major safety risk.

Either use a second, belt‑driven steering‑type pump dedicated to the plow/3‑pt, with its own reservoir and a small spool valve, leaving the factory steering circuit untouched.Or, if you must use the existing steering pump, insert a proper priority/flow‑dividing valve so steering always gets its required flow before any leftover goes to your lift valve. Before committing, work out whether the pump’s flow and pressure will give acceptable cylinder speed and force for your snowplow and 3‑point; undersizing will make everything painfully slow or weak even if it works.

There is a 7‑part hydraulic steering series that explains open‑center vs steering circuits, priority valves, and why simply teeing into steering lines is risky; it is written around mobile equipment, but the same principles apply to tractors and add‑on pumps: Hydraulic Steering Systems: Types & Uses You can also use this steering calculator to play with pump flow, cylinder size and pressure to see how fast a given power steering pump will move your plow or 3‑pt cylinder and what force you will actually get: Hydraulic Calculator