Loader is S/N BXY003XX We had a tilt cylinder rebuilt by local dealer and it is seeping after only a few days use, this is not the solved problem, well dealer rep came out to take a look. While looking at the machine he noted the hydraulics seemed too slow and suggested sending a guy out. Operator had mentioned that it did seem a little weak and something about banging in the system at times while returning bucket to level. Boss decided to have dealer send a guy out as the rep made it sound like there was a major failure coming any time. I did not have any time to check it out before hand as it is our main production machine and it it isn't running production drops and we know that is a NO NO! Guy come out and agrees it seems slow and there are several records of the code for the lift sensor being erratic, but nothing about the tilt where the problem seemed to be happening. He went through all the calibration steps related to hydraulics and it did cause the speed of the hoist to improve but operator still said the tilt would at times bang when it stopped and it would stop in the wrong place. Dealer mechanic said we should replace the lift sensor and re-calibrate again after that was installed before going further. So the next day I installed the new lift sensor and ran the calibrations for the hydraulic. Operator now says it's like a new machine, faster hydraulics and bucket kicks out at the right point every time and when it does it's very smooth and just a little click at the control levers when the magnet lets go. Almost seemed counter intuitive to be replacing a lift sensor when most noticeable problem seemed to be in the tilt circuit. Almost like changing a head light because the brake lights don't work!
Seen the same thing on a 992G. The issue is that both sensor signals are required to be present and "good" so that the Implement ECM knows where the bucket is in time & space. One of the things with the tilt is that it snubs as it comes close to the end of the stroke in both directions. However it only does it at a certain range of boom angles. So lose the boom angle sensor, even if it's only momentary, and the ECM senses a disturbance in the Matrix and all Hell breaks loose.
Lol!
As Nige already hit on......The tilt cyl bottomed out (or as far as it can go) when the boom is all the way down and when the boom is all the way up is in different positions due to the one end of the tilt cyl being bolted to the machine and the other on the loader frame (which is changing geometry). So the tilt needs to know the boom position at all times so it know when to snub properly. If it does not know this is slows everything down to help prevent damage from the tilt cyl hammering. It seems backwards but isn't when you think about how the tilt needs to know boom location to work properly
So you're telling me if this happens again I should not call the Cat dealer but call Doctor Who instead?
You may discover when you go to buy a replacement Tardis that your local Cat dealer is fresh out. I suggest you keep a spare one handy at all times.