View Full Version : Hydrolic pump/motor question

Bob Quale
08-06-2004, 07:35 PM
I have a hydrolic pump off of a log splitter. Would it be possible to feed this pump off the hydrolics from my tractor and use it as a motor? Then the motor could power a power washer or the like? I have not taken the pump apart yet, but it doesn't look like it is a piston pump. I am thinking a rotary pump?

Thanks Bob

08-06-2004, 07:44 PM
Some pumps can, some can't..

A gear rotor pump can, a recirculating ball or shaft pump won't..

There are a bunch of pretty nice motors on ebay right now (60-200). My neighbor has a dozen pretty large CharLynn motors.

I have been watching them, My plan is to run a hydraulic line through the shop, the shaper, big lathe and 50 ton press will run off the same pump.

Have you saw the flow proportional valves to control a motors speed?


[This message has been edited by ibewgypsie (edited 11-09-2005).]

08-06-2004, 07:44 PM
There are many types of hydraulic pumps. Don't assume from the appearance it doesn't have pistons. I could be an axial piston swash plate pump or any one of many different types. Some can be driven as motors and some not.

Bob Quale
08-06-2004, 07:50 PM
How can I tell if the pump can be used as a motor?

And if I were to by one off ebay, how would i know what to get? and hp rating?

Thanks Bob

08-06-2004, 08:22 PM
The ones on ebay ending here in a while have manufacturer specs on them.


[This message has been edited by ibewgypsie (edited 11-09-2005).]

Bob Quale
08-06-2004, 08:56 PM

I see the pumps on e-bay and they seem reasonable. However the power washer I want to run had a gas motor on it and turned around 3000rmp(i'm guessing). The hydraulic pumps only turn at 500-1000rpm. I don't think I can make it work. I wonder if I can buy a generic speed reduction and go off the pto? Maybe I'll start another thread about a speed reduction? But I really like the hydraulic avenue better.

any other ideas?


08-06-2004, 09:09 PM
Bob, I think there are two types of motors. Low rpm and high

Sounds like the ones on ebay are the kind I need, The other ones, well we had some at Dalton utiltities that ran 60,000 rpm..

OTHER IDEAL? how about a PTO driven generator? I saw one of them on there for 199...

[This message has been edited by ibewgypsie (edited 11-09-2005).]

Forrest Addy
08-06-2004, 09:31 PM
Why not run the washer pump directly from the tractor mechnaical PTO and forget about the invervening hydraulics. A V-belt pulley speed increaser is easy enough.

As for hydraulic pumps running as motors, most any will work but gear, vane, swashplate, and eccentric rotor wokr the best.

Like anything else there, has to be some kind of match of operating characteristics between hydraulic pump, motor, and load for things to work optimally. Study the subject of hydsraulics as vocabulary, theory, and physics before you start spending money and time building stuff.

08-06-2004, 09:42 PM
YOu know Forrest makes sense..

Using one of John S;'s flat auto serpentine belts..

You could rig up something pretty easy. He uses a cutting edge out of a pipe threader to make the serpentine grooves in pulleys..

I got a small Lawn tractor I am building things for too. (got a flat today, shucks)

It has the plug on the rear for the larger tractor PTO, ever had a cub cadet apart?

[This message has been edited by ibewgypsie (edited 11-09-2005).]

Michael Az
08-07-2004, 03:13 PM
David, I don't know if you have ever seen this Cub site but it has lots of info and a discussion board. The fellows there can probably help you with any info you need. I have two of the older bigger cubs but they are different than the cadets.