Hydraulic excavators usually couple engine power to (commonly) three hydraulic pumps rather than to mechanical drivetrains. The two main pumps supply oil at high pressure (up to 5000 psi) for the arms, swing motor, track motors and accessories while the third is a lower pressure (~700 psi) pump for pilot control of the spool valves; this third circuit allows for reduced physical effort when operating the controls. Generally, the 3 pumps used in excavators consist of 2 variable displacement piston pumps and a gear pump. The arrangement of the pumps in the excavator unit changes with different manufacturers using different formats.
For sale is a 2006 Kubota M8540 Tractor, 4WD, Kubota LA1353 Front Loader w/ Skid Steer mount bucket and 3rd function hydraulics, 8 Speed Shuttle Shift Transmission, 3 Rear Remotes, 85HP Kubota Diesel PRE EMISSIONS Engine, 5,246 Hours. Cranks right up and runs strong, lifts strong, Brakes are good. Has dents/dings/scratches and cosmetic imperfections but runs good! Has a lot of options and size for the price range!!.