Over a year ago many of you correctly diagnosed the lack of lowering on my 6610 3 point as a stuck control valve (https://talk.newagtalk.com/forums/thread-view.asp?tid=1138419). It took longer than expected to get a chance to work on it, but after pulling the lift cover and freeing the spool, the 3 point will now lift AND lower, so thank you all for the help!

Unfortunately, I seem to have now discovered a new issue (or an existing issue masked by the previous one). The hydraulic system appears to be pushing over relief constantly, except for when the 3 point is actively lifting. You can tell by the change in engine "tone" and by feeling the high pressure line coming out of the hydraulic pump.

I've pulled/cleaned all 3 spools out of the priority/unloader valve block (mounted on top of the lift cover) and re-installed after finding no obvious issues, but the behavior persists.

Does anyone have any suggestions for where to look next? I'd really like to avoid pulling the lift cover again if possible (it's a real pain with the cab).

Thanks!

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