Hi, I have read a few forum threads, but nothing seems to fit. It drifts down quite quickly with engine on or off, seat bar up or down. I can jack up the front of the machine using the tilt action, and it holds, so a one way leak?? I have inconclusively tested the piston seal: 1) capped the hoses at the cylinder, left it with a load - it holds fine, put back together 2) disconnected the cylinder side hose with my son operating the machine lifting the tilt, it oozed fluid..wasnt the gush I expected, but definitely a dribble. I dont know how much should come out, but I suspect none. So should I replace the piston seals as a first thing, or is there something more sinister at play? Been reading about spool valves, relief valves BICS etc shudder... Some tips would be great
It is possible you need to pull out the cylinder rod on one or both tilt cylinders and re-tork the the big nut on the rod end that is normally inside cylinder barrel.. Hopefully this solves the problem Have had this happen on T320 bobcat machine
Thanks Bobatack, nut is so tight I couldnt budge it..... I have bitten the bullet and ordered in a ram seal kit, so see how that goes. Fingers crossed!!
OK, so news seals in ram.....hot tip: when you put the new seal in place it will stretch and be too big to get back in the cylinder without damage....so, wrapit in a stiff material eg sheet of wet and dry, then clamp it with a hose clamp to push it into position, and freeze it. This will reset the memory of the seal and in it goes. But.... That wasnt the problem, tilt ram still drifts down exactly the same. So I am thinking the problem must be under the seat somewhere.... Any suggestions on where to look/test?
OK, some further information: I did the 'mid stroke bypass test' I watched a video about, basically disconnect and cap the cylinder end lines, start it up and put pressure on the ram to contact the ram. As the surface area on the ram side is less than the cylinder side, if the fluid is crossing over the ram will extend. My cylinder passed so I am sure now it is not the cylinder. I noticed other symptoms....when I apply a little pressure to the boom lift, but not enough to make it move, then lift the bucket tilt, the boom lifts! Its as if there is a crossover leak in the control valve. Also when the oil is cold, the boom and tilt rams are super jittery, dont move then drop 6 inches with a crash. I need to really go gentle on the pedals until it warms up. Dont know if all these are related....