Volvo EC300D

[RCP57]

So I've been wrestling a big problem with my valves... The one my Father inlaw made is very nice and it works perfectly(the bucket will stay up for days) BUT... it is large and at 30bar it is impossible to turn without pliers. I spent 12 hours the day before yesterday making my own valve from scatch that is much smaller and it does work a lot better but it is still stiff considering the size of it.

What am I missing???? There must be something simple that is done to this style valve that allows them to turn more freely under pressure. I tried drilling a small hole in the oil passage way on the pressure side of the plug(valve) to allow oil pressure into the top of the valve body but it didn't seen to help.

Does anyone know what we are not doing that needs to be done? Any help would be appreciated!!!


Thanks Reg