Problem solved, I think. The tank does not have a fill plug, but it does have one on the business end of the unit. It's the small, square headed plug in the picture close to the pulley. I used a small bulb syringe to fill it to the level of the plug. Plow lifts and lowers like a charm, all I need is some snow to push. Thanks all, for the help nudging me along to get this thing working. Guess it was just low on fluid, now I know how to check it.
