Yesterday we spent the best part of 3 hours trouble shooting the erratic operation of a quick hitch valve on a 30 ton Sumitomo excavator.
After dismantling the valve and picking pieces of black rubber out of the spool and valve body and wondering where the rubber was comming from, we flushed the lines and let the machine get back to work, after operating for 15 minutes and changing from bucket to ripper and then back to bucket the spool jamed again, During the second clean out cycle we found a small orange piece of plastic and that gave us the strong suspicion that the piston seals in the quick hitch cylinder had failed.
After we removed the quick hitch and dismantled the cylinder this is what we found.