problem with hidraulic gearbox, thus replaced on (probably unnecessarly) as lost power to maneuvre mower, now after 2 hours it maneuvrability reduces, I think the other gearbox has problems too, first I like to know if one can and how one can refill hidraulic oil to restore pressure? secondly I was told one could not repair the gearbox, I got a mechanic to look at my old box and he thinks there is no problem repairing the box, but would I get the parts? thanks for help George email gribi@bigpond.com