dsichewski
Well-Known Member
I've got a 420E with just over 1500 hrs on it. The cylinder rod had scoring on the rod and had the chrome flaking off on the underside of the rod. one day last week I noticed the cylinder drifting down as soon as I brought the cylinder all the way up and let the control go. It would drift down a good 4 inches fast and then slowly over time would drift down more. I thought oh the cylinder is leaking via bypassing the seals internally as I knew eventually it would. Sent the cylinder to a shop got it resealed, new rod and possibly a hone on the barrel not sure. reinstalled the cylinder and its still drifting...so now I'm wondering is it possibly the load/lock check valve gone bad? bad centering spool spring? or possibly the spool itself has a score in it from the chrome flaking off... I was wondering if anyone had a hydraulic schematic of the 420e phc serial number so I could trace the system and try and figure it out. Is the phc schematic the same as the schematic for kmw?