Vickers CM11-N02R20D-21 control valve

[ETD66SS]

Not sure if these will help but here is some information that I have on the CM11 valves. One is parts breakdown and the other is data sheet showing dimensions, model code, etc.

Thanks, yeah I downloaded a bunch of stuff from Eaton but I'll check those out.

I just went at removed the steering control unit:

Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet

I don't want to pull the steering control unit apart just yet.

I guess, what I need to know is, what happens when these things wear out? Does it put pressure back into the supply which might be causing my tilt cylinders to deadhead?

The steering control unit in the machine is a Char-Lynn RE25.291 I believe Eaton bought out Char-Lynn, and an Eaton series 10 SCU is an equivalent to this unit.

 

[oldnslo]

Yes Eaton owns Char-Lynn. Typically steering units are a real challenge to dismantle and reassemble properly. I will look later to see if I have any information on these.

For safety reasons Steering should always be the first item in your system or fed by a priority flow valve. Failing steering should not cause your machine to tilt.

 

[ETD66SS]

Yes Eaton owns Char-Lynn. Typically steering units are a real challenge to dismantle and reassemble properly. I will look later to see if I have any information on these.

For safety reasons Steering should always be the first item in your system or fed by a priority flow valve. Failing steering should not cause your machine to tilt.

Well, this machine was built in 1971, maybe they didn't have all the safety regulations they have today. The original parts manual I have for the machine has a schematic, and it shows the control valves being supplied directly by the PTO pump, and the steering control unit is after.

I rebuilt the HST unit on my Ford 1620 162-Reassembly-212 - Album on Imgur , so I am pretty sure I can handle this SCU. However, there is really nothing to rebuild, just seals. Seems to me, similarly to the spool valve, these things just wear out and you have to replace...

 

[oldnslo]

ETD,
Your CM11 is configured to provide 7 GPM bypass flow to functions down stream. On every system I have worked on the steering always was a priority so that if a function stopped flow upstream you still had steering and also brakes if hydraulic brakes. Agree didn't have the safety restrictions in the 70's they do today but still pretty sure pettibone covered there *** to make sure this machine always turned and stopped.

I looked and couldn't find any info on the steering unit based on the numbers provided. I do have info on 20 series but couldn't find a series 10. Typically Eaton Char-Lynn numbers are 3 digits a - and four digits possibly another - three more digits. Example: 261-1001-001

Can you post a picture of the schematic. It might help provide some answers or raise more questions.

 

[ETD66SS]

ETD,
Your CM11 is configured to provide 7 GPM bypass flow to functions down stream. On every system I have worked on the steering always was a priority so that if a function stopped flow upstream you still had steering and also brakes if hydraulic brakes. Agree didn't have the safety restrictions in the 70's they do today but still pretty sure pettibone covered there *** to make sure this machine always turned and stopped.

I looked and couldn't find any info on the steering unit based on the numbers provided. I do have info on 20 series but couldn't find a series 10. Typically Eaton Char-Lynn numbers are 3 digits a - and four digits possibly another - three more digits. Example: 261-1001-001

Can you post a picture of the schematic. It might help provide some answers or raise more questions.

I don't actually have a real HYD schematic, but I do have plumbing diagrams:

Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet

In the diagram for the outrigger cylinders, I have the caps (item 7) as I don't have the outrigger option on my machine.

I threw in the parts break down for the Char-Lynn SCU. I have been googling all night, I am not able to come up with anything that old. If I take it apart and the steel parts look good, I'll just measure the O-rings and seal and build my own seal kit.

Ok, I did some more googling, and came up with an Eaton part number for my Char-Lynn SCU, supposedly it's a 211-1012-003

 

[oldnslo]

ETD,
That 211-1012 is a series 6 SCU according to my old literature. I am attaching some information that I have for it.
In looking at the plumbing diagrams there should be line from the CM11 valve that goes back to tank and a line that goes from the CM11 to the SCU pressure port. I will have to study the CM11 "R" inlet option further to see what happens if the steering circuit dead heads. I have to run out for an appointment but will try and look at this more thoroughly later this morning.

03-303 is a technical document that explains how the steering unit works.
06-316 is the parts breakdown.

 

[ETD66SS]

ETD,
That 211-1012 is a series 6 SCU according to my old literature. I am attaching some information that I have for it.
In looking at the plumbing diagrams there should be line from the CM11 valve that goes back to tank and a line that goes from the CM11 to the SCU pressure port. I will have to study the CM11 "R" inlet option further to see what happens if the steering circuit dead heads. I have to run out for an appointment but will try and look at this more thoroughly later this morning.

03-303 is a technical document that explains how the steering unit works.
06-316 is the parts breakdown.

Thanks a lot for your expertise, much appreciated. I'll look over those documents.

EDIT:

I disassembled the SCU, I see nothing wrong inside, looks brand new... Imgur: The most awesome images on the Internet

This model looks older than the Series 6 in the literature, there are no large O-rings for the case, just one o-ring for the face flange, and a lip seal.

I'm not finding the root cause of the deadheading in the controls valve or this orbital, so hmm.

 

[bigdeano]

It would be interesting to tee a pressure gauge into the line from the CM11 to the steering valve.

 

[ETD66SS]

It would be interesting to tee a pressure gauge into the line from the CM11 to the steering valve.

I could do that when I get it back together. I have a 10,000 psi gage.

Well, I found some very minor damage on the inner spool:

Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet
Imgur: The most awesome images on the Internet

It looks like maybe a burr was picked up on all 6 grooves in the same location when turning left. There is no significant damage on the outer spool.

I have no clue if this could cause any issues, grasping at straws. The steering worked, just very noisy, whined a lot.

Now I have to find the correct seal for this SCU before I pull that out.

 

[oldnslo]

ETD,
On the CM11 end plate section was there an internal plug under the the port that connects to the steering valve? I have studied the CM data sheet and believe you have an "E" end plate which has the option for power beyond. Unfortunately I could not find a good schematic of the "R" inlet and "E" outlet in the data sheet. I believe but can't prove, that having the steering blocked should not cause the tilt function to shift one direction and stop. Only possible answer I can arrive at is if this was plumbed in series with no line direct to tank. Then if the steering in blocked I would expect the tilt cylinder to fully extend and not retract due to the differential area and pressure being basically equal on both ends of the cylinder.

I believe you will have to trace some lines to see where they go to confirm it is plumbed according to the diagrams in your manual.

Best of luck and let us know what you find or if you have any further questions.