I have noticed that the ballast box moves with the FEL curl even though the cut off valve is closed. On the X585 when the dealer installed the FEL they put in a cut off valve, I believe, in the the return line of the 3 pt cylinder. This valve is like a needle valve requiring several turns. It seems to work when I first start the tractor but as I start using the bucket the ballast box starts moving with the bucket dropping to the ground and causing me stress. Any thoughts on this and is there a way to physically lock up the 3 pt.?