Lifton -no drive

[Muz]

The pump is a variable flow output unit. Pressing forward on the footpedal must open the flow output in one direction, then further pressure on the pedal increases the swash plate angle in the pump increasing its output, so the machine moves faster. It must have a neutral position when the pedal is released, although in practice this needed careful adjustment to stop it creeping. When the pedal is reversed, either the pump uses the same output, but its direction is switched somewhere else, or it uses a secondary output which is plumbed to send oil in the other direction to the drives.

As I said, I have no idea as to the plumbing, I havent looked at one of these units for 10 years but the principle will be one of the above. So .. if youve established a working pressure somewhere, then it might be a control valve issue somewhere else at fault. It may also be that the pump generates a pilot pressure too, in order to operate a valve, it might not just be electronic control.

Do you know what pressures you should be looking for ? ... newer ones were 300 Bar or so and where did you test the pressure ?

[dmhk2005]

Once again, thank you, tested charge pressure at one of the check valves located on top of the pump, I am going to test output pressure tomorrow, should be about 240 barhowever, just one question, I understand that on hydrostatic drives you normally have a neutral arm and when it goes one way you get forward motion and when it goes over way you get reverse motion, however on this set up, the directional control valve lever controls which direction you go in, how does this work?, thanks again for your on-going help on this one