The Forestry Forum

Hey all. Has anyone ever adjusted the clutch on a 648D jd grapple skidder. My skidder still tries to move slightly when in the neutral position.  Can even notice when I go to start up the machine (slow cranking), like a pressure plate being too close to flywheel.

Is the machine actually moving or just surging a bit? Normal for JD power shift transmission. The oil film between the discs transmits some energy; more so when cold and the effect usually reduces as the transmission warms up. 
A large frame Ag tractor like a 4440 or 4450 shows this effect more dramatically, even when in park.

It seems to be more than a surge. It also is worse when warm. After working the machine for awhile and I shut off the engine, I have to wait for things to cool down before I can start up again. Heat and expansion makes the engine crank over very slow.

 If you pull up on the engine clutch disconnect lever under the dash -if it is the same place as a 640D it's on the left side- that will release the transmission from the engine. That won't fix the trying to drive, but should allow the engine to crank over better and start.
  You may have more than one thing going on, too, and that is caused by the hydraulic pump trying to build up to standby pressure. Internal leaks in the steering or brake valves are usually at fault here. If you suspect hydraulic problems, get a tech to put a set of gauges on the system to isolate your issues. 
  It sounds funny, but try shaking the steering wheel back and forth a bit while you try to crank it over. That will relieve some of the pressure buildup.

Thanks Oliver,
I will give that a try tonight and post what I find out. 

Thanks for the input Oliver.
 I lifted up the clutch disconnect lever after working the machine for app.15 minutes. It does seem to start better with less drag while turning over. Not much difference with the movement issue, however we are heading in the right direction. 
Thanks again.