Like kennyd says there is an allowance of leak down on loaders of "x" number of inches in a period of time. The main reason however for this is that it is a big liability to either leave a loader up when not operating or to claim it will stay up. For safety sake !!! put all of you attatchments on the ground when not in the seat and if you must work on something with the loader holding it up get yer self a chunk of angle iron and strap it to the
hyd cylinder. Also the ten series tractors did have the occasional poppet go bad and allowed for too much leakage (these are in the rockshaft housing)