I have a newly acquired T190. It came with a standard bucket so I have purchased and installed a new 4 in 1 bucket. Problem now is that the auxiliary hydraulics seem to work fine when opening the bucket but are very slow to close the bucket. When I release the electric switch on the RH handle after closing, the bucket wont hold position and goes limp. No problems are experienced when opening the bucket and it holds in the fully open position without fault. I tried my bucket on a friends machine and it works perfectly, I'm guessing there is a leaking seal or O-ring on the Auxiliary spool. Does anyone have any thoughts on my diagnosis? Thankyou in advance.
Also check the actuator for that circuit.
Ok, so I finally got to the bottom of this problem today. Turns out it was a damaged O-ring on the back of the male coupler inside the coupler block. Wow what a headache this caused me, and to think it was such a simple fix. I was about to dismantle the Hydraulic control valve but a mechanic at the dealer suggested I inspect the coupler block first. Very grateful for his help. When I removed the male coupler I found half of the O-ring but no sign of the other half???? It could have been pushed through the coupler block and back into the case drain line. I just hope it won't show up later having caused some other fault somewhere. Thanks DGODGR for the reply, and if anyone else has an opinion or preventative maintenance tip for finding my missing half O-ring, I'd love to hear it. Cheers.
you missing oring part may be still in the tubeline , or may have made it all the way back to the spool. it's basically "trapped oil" so it's probably still in the tubeline. disconnect the tubeline from the block and hose connection on the boom, blow compressed air back through the tube, and work your way back to the valve