Hi everyone. I have an industrial maintenance background, so some hydraulics experience from forklifts and manufacturing equipment, but not much with skid steers. I recently got an L553 from a friend that got it with a farm property that he purchased, that looks to have seen fairly hard use and has sat for some time. It had a rusted out hard steel hydraulic tube to the oil cooler, where it ran below the battery on the right side of the engine, and had lost a lot of hydraulic oil. After getting a hose to replace the rusted tube, and replacing the battery, I got it running and determined the drives seem to work well enough, boom works fine and will raise and lower, but the tilt would only move a very small amount, and the tilt cylinder is fully extended laying the bucket plat forward. We filled the hydraulic reservoir back up, hoping that might help, but not much change. Troubleshooting guide suggested the suction screen to the pump could be clogged, and it was pretty full of trash (silicone and metal shavings) so I cleaned the screen and reinstalled. Not much change after trying it then either. I unbolted the cylinder end, to rule out something being seized up with the bucket plate. Cracked the hoses to the tilt cylinder, retract is not pumping any oil with pedal movement, but extend side is. I should also mention that the safety module that disabled the boom was bypassed electrically, but it seems to be limited to locking out boom movement, and does not seem to interrupt the tilt cylinder. (I plan to fix that and put it back original once I am sure there are no deal killer level problems that I haven't found yet.) I have a digital service manual, parts breakdown, and owners manual, and I've been looking through them for details, but I'm thinking the valve for the bucket tilt is the issue, stuck or maybe the linkage could be not adjusted correctly, if that's possible? Given that the boom is working so well I'm ruling out anything major like the pump, but the shavings in the suction screen have me a bit spooked now. If anyone has experience with this issue, and has some advice it would be much appreciated.
Look and see if there's a lockout solenoid on the bucket tilt valve like there is on the boom hoist. You say it's electrically bypassed some way for now. If the solenoid is bad it won't open up and let the spool move. Check that first. Unscrew the solenoid and see if the bucket works. If it does then there's your issue. If that isn't the issue check all the linkages. They can rust and seize up from sitting up. Disconnect the linkage at the spool valve and see if it's all froze up. While you have the solenoid unscrewed {if there is one} take a pry bar or something and see if the spool valve moves freely. If not there's your issue. There may be rust build up on the bottom of the spool or something like that. Have the boom on the ground for this as stuff can move with the solenoids out for testing. Don't be where you can get mashed by the boom of bucket. Do all of this ENGINE OFF. My bet is the linkage is froze up. I'd check that first. Good luck.
Thanks tractormech. There is such a solenoid on the boom schematic line, but I don't see anything like that in line with the tilt cylinder.
I don't think they electrically locked tilt I would guess a linkage issue could even be junk under the pedal if it has auxiliary hydraulics make sure that valve is not activated or stuck that can make them do funny things
I think this is likely at least part of the issue, there is a mixture of leaves, dirt, oil, twigs etc. that I have been digging out around the e-brake linkage and under the drive motors. The tilt and boom linkages go under the left hand motor. The pedal itself seems to move freely though, and the tilt cylinder moves a small amount. Kind of having to chip away at it when I have a bit of free time. I'll update as I find more out.
Sent you a PM
Got a chance to work on it this evening. Scooped a bunch of mud, twigs, debris out from under the drive motors, so I know for sure the linkage is free at the valve now, which I can feel below and behind the drive motor. Found a rock in that area, so I thought that might be the problem, but once I started it back up, no change. Time to go back and study the hyd schematic some more.