Help figuring out the specs of hydraulic motors.

[4570Man]

A buddy and I are wanting to build a tracked vehicle. Although it might have a blade on it it will serve no purpose except to have fun. I have the hydraulics out of a skid steer that was sold for scrap. I have the wheel motors, the pumps, and the valves. I know the motors had a gear reduction, but the gears were scrapped so I don't know what the ratio was. I need the rpm and toque numbers. What do I need to do to figure this out?

 

[oldnslo]

To figure motor torque & RPM you will need to know the motor displacement in either cc/rev (cubic centimeter per revolution) or CIR (cubic inch per revolution). With displacement you can calculate RPM based on inlet flow and pressure based on pressure drop across the motor.

 

[4570Man]

How do I figure out displacement? I have the pump off the skid steer, but I don't know the flow or pressure.

 

[bigdeano]

Do you know the model of the skid steer it's off of? Maybe you can track down what the motors are if they're aren't any numbers on the motors.

You can attach 2 hoses to the motor and put them in a bucket of oil. Turn the motor until all the air is out, then put the discharge hose in another container and see how many turns it takes to fill it. A little math will tell you the displacement. I wouldn't worry too much about the pressure rating. On a skid steer it will be very high, probably like 4500 psi.

It's probably a piston motor, so I don't know if it will operate properly as a pump like I described above, but it's worth a try.

 

[4570Man]

It was a Mustang skid steer. The exact model is unknown. It was relatively small like possibly a 940.

 

[oldnslo]

Are there any numbers stamped on the motrs any where? If Eaton the numbers could be stamped on the mounting flange. Example 174973-001

Possible these would be OEM specific so they might not help also.

 

[4570Man]

I haven't seen any numbers. I guess I should go clean them up and look over them closer.

 

[4570Man]

Here is all the markings on the motors. That doesn't seem very helpful, but hopefully someone might know something about it.

 

[wdchyd]

The model code on those will be on the edge of the mounting flange stamped

 

[oldnslo]

Cessna was purchased by Eaton years ago so finding the person with info on those ccould be a challenge.