loader valve help

[FF110]

I replaced the loader valve on my jd 2550 with a prince valve and am having problems with the bucket raising up as the tractor runs. It is not very fast but over a few minutes it has raised up quite a bit. It is a closed hydraulic system so I put a cc plug in the valve and have tried to adjust it with no luck in fixing the problem. I also checked the cables leading from the cab to the valve and do not seem to be putting any pressure on the valves. Any ideas on how to fix this problem would be greatly appreciated.
Thanks

 

[J_J]

Did you install a no relief valve in the relief port?

Here is an excerpt from Prince.

PLEASE NOTE that this closed center option does not provide for the drain off of standby spool leakage. This can allow a very small amount of oil to enter the work ports when in neutral. Closed center option is often used with no relief. Review application.

If your valve is an LVT, then the no relief plug is 660280004

 

[FF110]

I did not. I talked to the people at surplus center and they didn't say that I needed it. I will try the no relief plug. Thanks for the help