Bleeding the ripper hydraulic cylinders

[Cle Elum John]

I need some help bleeding the ripper hydraulic cylinders. The ripper does not have much push down force when the cylinders are almost fully extended. It worked well the last time it was used. No leaks anywhere. It has a 4in1 bucket and all that works fine.

Specifics:
It is 450 no suffix
The clamshell on the 4in1 and ripper both use the same control valve and there is a diverter valve to switch between the two.
The ripper has two nearly vertical hydraulic cylinders.
The cylinder is on the top side, the rod is on the lower end at the ripper.
There is a bleeder port on the upper end of the cylinder.

I have been fully extending the rod, cracking the bleeder port and then fully retracting. It spits out air bubbles, fluid and a little foam. The bleeder port is tightened and then the rod is fully extended again. I have gone through the process a number of times. I am still getting more air and the push down force on the ripper is not much better.

Any suggestions?

[Jim B]

Good morning John,

I take it this ripper has been on this crawler right along, not a new installation. Is this a 3100/3110 JD ripper? I may have missed them; however, I don't find any bleeders in the parts catalog for the 3100/3110 or bleeding instructions in the Operator's manual OMT64181 when I look. Manually bleeding hydraulic cylinders is not a step that has been required for many years. There should be no need to bleed those double acting cylinders. The cylinders should self-bleed any air from them after a few cycles.

Is the hydraulic reservoir at the proper level? Is the diverter valve fully changing position from bucket to ripper? Does the bucket function have strong, full function? Did you have trouble with one of these valves in the past?

Run the back of the crawler up on something so you can fully lower the ripper (pull the shanks if needed). Make sure the "bleeders" you have been using are closed tight. Cycle the ripper full strokes a few times, keeping watch of the reservoir oil level. The air should work its way out.

There is the possibility that the packings are bad in one or both of the ripper cylinders and bypassing when you try to apply down pressure.
Best Regards,
Jim