H-DS -- How Does it Work?

[Rockin' G Ranch]

As most of you know by now I have a Kubota L4740 HST that I am learning how to operate. This question is about the Hydro Dual Speed (H-DS). The lever is on the L side of the steering column. Push it down for Slow and pull up for Fast. When I push down or pull up on the lever I don't feel anything or notice any change in the tractor operation. How does this feature work? Is it an electrical or cable? Should it stay down when I push down the lever?
Thanks for the help.

 

[VA MTN MAN]

Try pushing it while moving and you feel it either slow down or speed up. It works like making the transmissiom a 6 speed instead of the 3 it is. Hope this helps.

 

[PHILIP8N]

It is a center normal position - momentary up or momentary down switch. Dashboard will have turtle or rabbit to show which position you are in. The switch controls a 2 stage motor. When moving at full throttle / full speed, you should defentely be able to tell a difference between low and high when switching back and forth between the two. Philip.

 

[crazyal]

Do you see the turtle and rabbit change when you pull or push the switch? You should also hear a beep.

 

[Texas Fella]

It works electrically. By moving the switch (lever) you send a signal to the ECU which sends a signal to a solenoid on the HST. The solenoid then chages the angle of the swash plate on the motor side on the HST, thus changing the displacement of the HST motor. More displacement (higher volume) more torque, less speed. Less displacement (lower volume) more speed, less torque.

 

[PHILIP8N]

Get a Kubota brochure, at dealer, by mail (thru website), or download. Alot of your questions are answered in good detail here, with pictures. On the Kubota website there used to be a nice video for the operation and function of the HST+. Philip.