hydro lift cylinder
 

i converted my 129 to hydro lift this winter. when i lift a attachment all the way up and let it sit, it slowly starts to fall down. i was thinking it was just from the cold but it still does it. whats wrong with it?

My bet would be the seals on the piston inside the cylinder are bypassing.

That's possible, but I'd try rebuilding the control valve first. The O-rings in there get pretty worn after awhile. None of them will stay up forever; every hydro lift I've had sinks down after awhile.

How long does it sit before it starts to go down?

with the dozer blade on the front it would after about 5 seconds but now with the cultavator on the back it just slowly sinks right away