Hydraulic issue M1-55dt

[Iain]

Hi

I'm having hydraulic issues with a M1-55dt which I believe is equivalent to a M5950DT-S 4wd. Intermittently the 3pl and loader do not work. Totally non responsive. No strange noises that I have noticed. Power steering is fine. Shutting down and restarting sometimes temporarily fixes the issue. Any ideas what this could be?

 

[100 td]

Air in suction line to hydraulic pump, blocked filters or strainers, orings or cracked/damaged/leakingflexibile lines on suction side of pump or between pump and filters, or between filters and sump/tank depending on your tractor. Low hydraulic fluid level.
EDIT: Or if single pump operation, flow priority valve......but I would expect a dual pump, but haven't looked.