3 point hydraulic drifting on ex2900

[alltherage]

I have a finish mower on the back right now and I've noticed that every minute or 2 the hydraulics kick on and raise it. It's drifting down. This is during idle and I've never had this problem before. If I shut the tractor down I can hear the mower creak as it slowlyyyy sinks. The last 2 years I've been using a rather large snowblower in wintertime but it weighs less than the 3 point is rated for. 100 to 200 pounds less. I only use it on my driveway and it's not very often. Is there an adjustment or have i ruined a seal or something? This is a 2011 with 180 hours on it. The hydraulics have been used very little, just finish mower in the summer and blower in the winter. sporadic loader work but essentially this tractor has been babied. thanks for any help

 

[yotehunter66]

I wonder if the load check is leaking by.

 

[yotehunter66]

View attachment Cub Cadet Yanmar Ex2900 Ex3200 Ex Series Compact Tractor Service Manual.pdf

 

[alltherage]

the blower is 869 and the mower is 610. the 3 point is rated for 1100. here are some things i noticed...it only seems to do it if the lift arms are well over center or all the way up. it doesn't seem to do it if the lift arms are a bit over center or below. Also, it doesn't matter if i raise the rpms or if i'm at idle. I also checked to verify with a measuring device that it was actually sinking, and it was. It's doing it every 40 seconds or so. Like I said, if the arms are raised up only a little bit, so the mower is off the ground completely, it doesn't do it from what i've seen. ideas? and thanks so far

 

[yotehunter66]

Does it drift down with no load on it? My first guess would be the seal on the load check. Maybe someone else will chime in with a suggestion.