My backhoe, Case 580se, sits around most of the time. I've repacked most of the cylinders but not the bh bucket cylinder and its been seeping for several years. When I recently had it out to dig up multi-flora rose along a fence line, the seals on the bucket cylinder gave out. I took the cylinder apart and noticed unusual color on the piston seals, sort of rust brown. Im just wondering what could have caused this discoloration or brown deposits on the piston seals? Also does the milky color of the hydraulic fluid indicate the presence of water in the oil ? Thanks ! ?
I think cylinder seals can get discolored from heat and friction but it looks like you have a lot of water in the hydraulic fluid. Need to drain and flush system as best you can and investigate where water could be getting in.
While it’s out, look in the bore of the cylinder with a light, may have rust in it, if you had water in the oil and hasn’t been used in awhile. When I was rebuilding my skid, I was doing a lift cylinder and tilt cylinder at the same time. I did the tilt cylinder first and didn’t look inside very well. As I was doing the lift cylinder, found some rust inside for about 4” and threw a ball brush through it and it cleaned up nicely. Got it back together and the tilt still drops pretty quickly and ruined a set of new seals, I expect. Need to take it apart soon as it’s getting aggravating. If there is water, need to get it out ASAP!
It’s hard to see down this tube of mirrors but it looks ok , there is some crud near the threads which the piston probably doesn’t reach. Definitely need to address that milky hydraulic fluid though. Most likely it took in water via the bad seal on the dipper cylinder, this has since been replaced. Do folks park their backhoes with the boom extended vs upright to prevent possible inflow of moisture from rainwater into the dipper cylinder?
If the wiper seals and gland nut seals are good shouldn't really get water in the cylinders. Otherwise every excavator out there would have contaminated fluid.