hydro buzzing

[Guest]

I have a sovereign 18hp. when I use the hydraulic lift the thing hums or buzz's and when it is all the way up or all the down if I don't let go of the lever it gets louder. Now I just changed the hydo oil and it is completely full so I know that is not the problem. Is this the norm? Any fixes?

[swood]

Hello Mike, Was it making the noise before you changed the fuild?? Most hydro pumps makes noise similer to what you are discribing and unless you let up on the lever it forces the bypass valve to open which will make more noise. Can you tell us alittle more about when it started and if so how much worse has it gotten?? If it wasn't doing it before you changed the fuild just maybe it has some air that needs bleeding out. If it indeed is a humming noise I wouldn't worry about it but if a whinning noise then I would be concerned. Maybe others can help but I can't give an honest answer other then it sounds fairly normal to me. Take care, >>->happyjack<-<<