Bottlerocket

[chris wiggins]

Need some help
I've got a 2008 John Deere 4105. Everything worked fine other than I had a leaking boom lift cylinder. Replaced the O-rings . After this repair, my three point settles down when it's set form 0- 1/4 up. If I raise it above 1/4 it stays where I set it. Checked my fluid all is good. Tried bleeding the line going into the block to see if I had air in the line. Didn't see any evidence of air.
Any ideas on what I can check next?

 

[Cpjlube]

Simplest answer is there is still air in the lines. Just let it run, work every hydraulic valve back and forth. Give it ten or fifteen minutes to circulate.
Any air that was in the cylinder after rebuild may still be stuck somewhere.

Chuck

 

[chris wiggins]

That's what I keep thinking. I've worked everything multiple times. I have even mowed with it for several hours by keeping it set with a wire tied to the lift lever. I'll keep going with it to see if it will work the air out of the system.
If you think of anything else, let me know. I appreciate any help I can get.

 

[J_J]

The air should have been purged by now unless you are sucking air in the suction hose.

The cyl bore might be worn in certain areas and may allow leakage or settling .

 

[Cpjlube]

I'm assuming the boom cylinder is on the loader.

Is the loader quick detachable? Maybe take the loader off and try again?

I'm not sure if open or closed center hydraulics are different with air pockets. Not sure if the 4105 is closed center but I think it is.

Chuck

 

[Tx Jim]

I'm not sure if open or closed center hydraulics are different with air pockets. Not sure if the 4105 is closed center but I think it is.Chuck

JD 4105 is open center hyd's. Open & closed center hyd's both disperse air through operation of hyd functions.

 

[chris wiggins]

I'm assuming the boom cylinder is on the loader.

Is the loader quick detachable? Maybe take the loader off and try again?

I'm not sure if open or closed center hydraulics are different with air pockets. Not sure if the 4105 is closed center but I think it is.

Chuck

It is a quick attach loader. I'll try taking it off to see if it makes a difference. I'm not sure about the open or closed center hydraulics either. Something simple (o-ring replacement on the loader), you wouldn't think would create such a problem. I want to get this figured out for when I have to redo other cylinders.

 

[chris wiggins]

Tried taking the loader off, didn't make a difference. My problem ended up being an adjustment where the lift lever mounted to the shaft that goes to the rockshaft control valve, There are 4 disc springs that keep tension. All I had to do was tighten the nut for more tension.
So much trouble for such a simple fix.
Thanks for all the input.