Case Drain – KX41-2V

[whitetiger]

The flail mower I would like to rent has 2 connections, a pressure line and a low pressure tank return line (case drain? or is that something else?). But since it has 2 connections I expect a lot of oil going to the return line.

There is a lever on a directional block under the RH cover of your machine that you MUST place in the low-pressure return to the tank. Its other position runs the oil through the Aux control valve.

One position is for operating pressure to either of the 2 ports for a thumb. The other position is to return oil directly into the tank rather than pushing it through the control valve. It is used for an orbital motor or a breaker/hammer etc.

 

[xenophon.nl]

If it only has two lines it is a basic (unidirectional?) motor circuit with pressure out low pressure tank return and does not have a case drain. A case.drain is an additional "zero pressure third line"..

You started this thread saying the motor required a case drain. What made you think that?

Dan

It seems that I misunderstood a couple things, they said it needed a pressure line and a 'free return line', of which the last I thought they meant a case drain.

But as you say there are only 2 connections, so I do not need a case drain.

Then they said there should be a valve that would turn my double acting auxiliary connection into a single acting one.

This valve I cannot find. But do I really need a single acting aux connection? Can I not just always actuate in the same direction?

 

[GreensvilleJay]

you could but WHEN ( and you will..) try 'reverse', you'll probably bust an expensive piece of kit.....

 

[TheOldHokie]

It seems that I misunderstood a couple things, they said it needed a pressure line and a 'free return line', of which the last I thought they meant a case drain.

But as you say there are only 2 connections, so I do not need a case drain.

Then they said there should be a valve that would turn my double acting auxiliary connection into a single acting one.

This valve I cannot find. But do I really need a single acting aux connection? Can I not just always actuate in the same direction?

If I understand Whitetiger the lever does mot make the valve single acting. It changes the second outlet to direct tank return rather than back into the valve stack. That is what your mower requires.

Dan

 

[TheOldHokie]

you could but WHEN ( and you will..) try 'reverse', you'll probably bust an expensive piece of kit.....

No he cant. Read what Whitetiger said.

Dan

 

[GreensvilleJay]

re: Then they said there should be a valve that would turn my double acting auxiliary connection into a single acting one.

I assumed this was a normal double acting valve...NOT some 'fancy' special valve.

 

[TheOldHokie]

re: Then they said there should be a valve that would turn my double acting auxiliary connection into a single acting one.

I assumed this was a normal double acting valve...NOT some 'fancy' special valve.

From Whitetger's description the selector lever is not part of the control valve. Its a simple 3 way selector valve external to the control valvr.

In position A it connects the hydraulic outlet to one of the two work ports on the control valve.

In position B it connects the hydraulic outlet straight to tank.

Simple and effective way to connect a high flow motor.

I also suspect the hydraulic system on the excavator is closed not open center and the valves are load sensing.

Dan

 

[xenophon.nl]

There is a lever on a directional block under the RH cover of your machine that you MUST place in the low-pressure return to the tank. Its other position runs the oil through the Aux control valve.

One position is for operating pressure to either of the 2 ports for a thumb. The other position is to return oil directly into the tank rather than pushing it through the control valve. It is used for an orbital motor or a breaker/hammer etc.

Very exited I opened up the cover, but I see nothing there of a valve. I will include some pictures, I also marked the cover, is that what you meant?

From Whitetger's description the selector lever is not part of the control valve. Its a simple 3 way selector valve external to the control valvr.

When I follow the aux lines they both connect on top of the control valve, so I actually really doubt I have a lever somewhere, or it would be in the valve body or something.

 

[GreensvilleJay]

If the posted hydraulic diagram is accurate for his 'Dutch' machine, I don't see that 'selector valve' that WT was referring to in it. There is the 'normal vs JDeere' one, shown in the lower left.
One valve centered in the diagram marked 'service' going to unconnected 'XX'. it appears to be a normal valve though.
perhaps what Wt was referring to is n 'American' only version or an 'option' ?

 

[TheOldHokie]

Very exited I opened up the cover, but I see nothing there of a valve. I will include some pictures, I also marked the cover, is that what you meant?



When I follow the aux lines they both connect on top of the control valve, so I actually really doubt I have a lever somewhere, or it would be in the valve body or something.

I found a copy of rhe operators manual for your excavator and there is no mention of such a valve. Yet two different dources have told you about it. Very odd.

Perhaps its an option you have to purchase and add. Hopefully WT can clarify.

In any event its not a case drain just a direct to sump motor return. It should not be hard to roll your own - either a diverter installed in one of the work port lines luke WT described or just a third outlet plumbed to tank.

Whats inside the hinged door above the cover you removed?

Dan

 

[Henro]

The workshop manual I have a copy of has two hydraulic system diagrams. One says North American version only. I did not compare them to see what the differences might be.

I will try to include screen shots of the two diagrams. Hopefully they will be legible.

Edit: After posting I just noticed that the first diagram is not the 2V model… Best I can do…

 

[TheOldHokie]

The workshop manual I have a copy of has two hydraulic system diagrams. One says North American version only. I did not compare them to see what the differences might be.

I will try to include screen shots of the two diagrams. Hopefully they will be legible.

Edit: After posting I just noticed that the first diagram is not the 2V model… Best I can do…

View attachment 136577 View attachment 136578

The operators nanual I downloaded is also KX41-2 not 2V.

Both of Henro's diagrams show a symbol I do not recognize on both the A and B work ports of the service valve. The symbols are on different ports depending on the durection the spool is shifted. Something is going on there.

Dan

 

[TheOldHokie]

The workshop manual I have a copy of has two hydraulic system diagrams. One says North American version only. I did not compare them to see what the differences might be.

I will try to include screen shots of the two diagrams. Hopefully they will be legible.

Edit: After posting I just noticed that the first diagram is not the 2V model… Best I can do…

View attachment 136577 View attachment 136578

Those are top level diagrams. Does the WSM have a section detailing the operation of the service valve?

Dan

 

[Henro]

The operators nanual I downloaded is also KX41-2 not 2V.

Both of Henro's diagrams show a symbol I do not recognize on both the A and B work ports of the service valve. The symbols are on different ports depending on the durection the spool is shifted. Something is going on there.

Dan


View attachment 136580

Dan, I think those circles hold numbers, and the numbers are referred to the chart on the right hand side of the drawing for orifice size… the reason I think that is on a different drawing I saw a circle like that but it had a 12 in it instead of an 11 or a 1.

 

[TheOldHokie]

OK

Dan, I think those circles hold numbers, and the numbers are referred to the chart on the right hand side of the drawing for orifice size… the reason I think that is on a different drawing I saw a circle like that but it had a 12 in it instead of an 11 or a 1.

OK - my vision is not what it used to be

That number is typically a reference to a detail drawing some place else.

Edit: never mind - I did not read your post closely enough....

 

[GreensvilleJay]

hmm lines in circles do appear to reference the 'orifice size' chart to the right.
I had to zoom 300% to see.
perhaps there's internal flow restrictors in that valve ? it looks like a 'modified' double acting spool valve, has both straight and criss-crossed positions.
be nice to see service manual for this 'service' valve.

 

[TheOldHokie]

hmm lines in circles do appear to reference the 'orifice size' chart to the right.
I had to zoom 300% to see.
perhaps there's internal flow restrictors in that valve ? it looks like a 'modified' double acting spool valve, has both straight and criss-crossed positions.
be nice to see service manual for this 'service' valve.

Three positions with straight and crisscrossed flow is the diagram for a standard double acting (4 way) control valve.

Dan

 

[whitetiger]

I did not realize that you are not in NA, the valve may not have been available on your country's version.
Manufacturers use different electrical and hydraulic components depending on which market the unit is built for.
This machine may very well not have the valve.

 

[xenophon.nl]

I did not realize that you are not in NA, the valve may not have been available on your country's version.
Manufacturers use different electrical and hydraulic components depending on which market the unit is built for.
This machine may very well not have the valve.

I am starting to think my model does not have the valve. So what can I do to connect the mower? Just use the double acting valve? Or connect one aux port to a return line? But where and how can I ‘T’ into a return line?

 

[whitetiger]

If there are not 3 hoses on the hydraulic motor, you can run it by plugging the 2 hoses from the mower to the Aux couplers of your machine. Ensure you are spinning the mower in the correct direction and watch your hydraulic temperature light.