Johndeer 410d hyds loading up

Looking over our backhoe we purchased other day, was purchased as is An was no battery in it, well put battery in an started it up an noticed that front bucket automatically started tilting over with out holding control lever, Was picking hoe up off the ground, though there was a bad relief valve so we replaced with new, didn’t help, so we took the whole valvebody off hoe an took to deer , they said it looked ok, replaced control valve back to hoe am still tilts front bucket over at start up an hyds seem to stall an load up on there on?any ideas. Could be a crack I’m contr valve body?

Just like Cat, we Deere people always need a serial number. Based on your description I bet your serial number is under 801199. If so see illustration. You said you replaced a relief valve. Was it the one shown below ("K") or the system relief?

My serial number is 782174. An the relief valve that was replaced as the rear one with valve on tractor so that would be letter H valve. I mean soon as tractor starts up it’s automatically tilts over an try to let bucket down, soon as ya pull the controls back to lift bucket or curl bucket back up the system works fine till ya let go of handle then hyds dead head again an loads up motor

Check the seals I show in the graphic.

Orings an back up rings seam
To be fine. Even replaced with new just to be sure