Wiring in lane shark on l3902…

[Jasonized]

Maybe try listening and asking for a while instead of teaching.

The tank return on a power beyond valve carries overpressure flow AND in most cases oil returned on the work ports. This isolates the actuators from downstream devices which is what you generally want.

In the case of the loader valve on an LA525 (and most other Kubota loaders) the lift spool sends return oil to power beyond which puts all downstream devices in series with the loader lift cylinders, That has the potential for undesirable actuator interactions.

The same is true of the third function valve,

On a LA525 loader the return oil from the curl function is also sent to tank and PB is blocked.

On a LA525 the return oil from the extend function is redirected to the base end of the cylinders for regenerative speed up of the cylinders (aka fast dump) and PB is blocked.

Those are all interactions that Lane Shark never mentions.

Dan

Actually Dan, I am listening and learning. I integrate and then say what I’ve seen, so I can get input from others to fix my understanding or clean it up. If I don’t say anything, you can’t correct it! So bottom line, no, I’m not trying to teach you. Sorry if it sounds like I was.

if your explanation of the loader function is correct, then that also explains why land pride has the install in front of the loader, because with it there, I can use the loader, curl the mount and change the grapple all at the same time. If it were downstream then I would have to run the grapple only when not moving the loader. Not as fun!

 

[TheOldHokie]

Actually Dan, I am listening and learning. I integrate and then say what I’ve seen, so I can get input from others to fix my understanding or clean it up. If I don’t say anything, you can’t correct it! So bottom line, no, I’m not trying to teach you. Sorry if it sounds like I was.

if your explanation of the loader function is correct, then that also explains why land pride has the install in front of the loader, because with it there, I can use the loader, curl the mount and change the grapple all at the same time. If it were downstream then I would have to run the grapple only when not moving the loader. Not as fun!

I dont deal in mis-informstion. My description of the loader valve operation is straight out of the WSM.

Your third function analysis is partially correct. If placed after the loader valve the loader boom function will not impede the 3rd function at all but thetwo functions will interact exactly as thet do with third function ahead of loader. The bucket function will mostly block the third function. Since the bucket spool has some metering capability you can try to find a sweet point where only a portion of the neutral flow is being diverted and get both functions to work simultaneously. Its a tedious balancing act. Much better to have the third function ahead of the loader.

Dan

 

[Jasonized]

Okay then…. I‘ve got the loader side plumbed. Brackets fab’d, hoses run. Getting ready to mount a diverter valve and run hoses….

Now, tracing PB from the loader, it goes to the pump block. Cool. So I should be able to re-route that line to the diverter, and run the closed position line back to it. The open position will run to the qc for the power line to the lane shark…

Then just route the return line to the tank…. Does it matter which port I end up using on the pump block? It looks like it has two return ports, one labeled PB, the other Tank..
From looking simply at the functions, they are the same, yes? so the motor return to tank can go on either one?

thanks!

 

[TheOldHokie]

Okay then…. I‘ve got the loader side plumbed. Brackets fab’d, hoses run. Getting ready to mount a diverter valve and run hoses….

Now, tracing PB from the loader, it goes to the pump block. Cool. So I should be able to re-route that line to the diverter, and run the closed position line back to it. The open position will run to the qc for the power line to the lane shark…

Then just route the return line to the tank…. Does it matter which port I end up using on the pump block? It looks like it has two return ports, one labeled PB, the other Tank..
From looking simply at the functions, they are the same, yes? so the motor return to tank can go on either one?

thanks!

No - they are not the same. You want motor return going to tank - bottom front on the block.

Dan

 

[Jasonized]

No - they are not the same. You want motor return going to tank - bottom front on the block.

Dan

okay, thanks. Just checking!

 

[Jasonized]

Just out of curiosity (I’m that type of guy), what’s the difference? Is there a restrictor or something in the PB return port?

 

[TheOldHokie]

Just out of curiosity (I’m that type of guy), what’s the difference? Is there a restrictor or something in the PB return port?

Tank goes straight to tank with minimal restriction and near zero back pressure.

Power beyond goes to and through all down stream devices e.g backhoe valve, remote vslves, and 3pt valve. The circuit has more natural restriction and when a downstream device is operated pressures can go to several thousand PSI and flow can go to zero e.g totally blocked.

Dan

 

[Jasonized]

Hmmm... Guess I didn't ask the question properly.

At the tank... i.e., after all the devices, etc, where it ends at the tank... at the inlet ports to the tank... is there a difference between the two inlet ports? Does the PB return have a flow constrictor or something? Or do both inlet ports go directly into the tank, and the labels are just for reference?

Cheers!

 

[TheOldHokie]

Hmmm... Guess I didn't ask the question properly.

At the tank... i.e., after all the devices, etc, where it ends at the tank... at the inlet ports to the tank... is there a difference between the two inlet ports? Does the PB return have a flow constrictor or something? Or do both inlet ports go directly into the tank, and the labels are just for reference?

Cheers!

At the end of the line they both dump into the reservoir. But that is meanunhless:

The tank port goes straight to reservoir, does not pass GO, has no shutoffs and provides the least restrictive route to end of line possible.

The PB has many restrictors in it - they are called HYDRAULIC VALVES and CYLINDERS. They have smaller oil passages, move loads, and they can and do creste massive back pressure and even SHUTOFF the flow completely.

Thats as clear as I can make it.

Dan

 

[Jasonized]

At the end of the line they both dump into the reservoir.

Dan

How they are used is different, absolutely. But what I was curious about was if there was a physical difference at the tank, and it appears that the answer is no.

So the answer to my original question is: No, there is no physical difference between inlet ports at the tank.

Convention declares the PB inlet be used as the return line for various valves, motors, etc. But the tank doesn't seem to care. So apparently I could probably (if I was really being weird) swap the PB and Tank hydraulic lines where they enter the tank, and nothing would change. (Well, anyone who had to later work on it would cuss me out, but I'd probably be gone by then anyway!)

And no, before anyone jumps to conclusions, I am not going to do that. I generally stick with conventions unless I have a reasonable reason not to.

But since I don't have an actual device that I am willing to take apart to see how it works, I asked. That's how I learn; I usually take things apart to see how they work so I understand them at the physical level. I am not a black box kinda guy. Actually, I'd rather have physical designs on the various pumps, valves and motors (well, motors I already understand) so I can understand them implicitly, instead of asking questions. But I haven't found anything on them yet...

Cheers!

 

[GreensvilleJay]

It kinda sounds like his tank has 2 ports , one labelled 'drain' and one 'PB' ( picture or drawing would help ) . I can see there 'may' be a difference in size of the ports as 'drain' fluid would be little, PB could be a lot ??

 

[TheOldHokie]

How they are used is different, absolutely. But what I was curious about was if there was a physical difference at the tank, and it appears that the answer is no.

So the answer to my original question is: No, there is no physical difference between inlet ports at the tank.

Convention declares the PB inlet be used as the return line for various valves, motors, etc. But the tank doesn't seem to care. So apparently I could probably (if I was really being weird) swap the PB and Tank hydraulic lines where they enter the tank, and nothing would change. (Well, anyone who had to later work on it would cuss me out, but I'd probably be gone by then anyway!)

And no, before anyone jumps to conclusions, I am not going to do that. I generally stick with conventions unless I have a reasonable reason not to.

But since I don't have an actual device that I am willing to take apart to see how it works, I asked. That's how I learn; I usually take things apart to see how they work so I understand them at the physical level. I am not a black box kinda guy. Actually, I'd rather have physical designs on the various pumps, valves and motors (well, motors I already understand) so I can understand them implicitly, instead of asking questions. But I haven't found anything on them yet...

Cheers!

I dont understand what you are saying. There is no way to change those circuits. They are an integral part of the tractor. The outlet for the power beyond is part of the 3pt valve.

 

[Jasonized]

It kinda sounds like his tank has 2 ports , one labelled 'drain' and one 'PB' ( picture or drawing would help ) . I can see there 'may' be a difference in size of the ports as 'drain' fluid would be little, PB could be a lot ??

I posted the image from the loader install guide up above, about time 8:43?
The ports look all the same size.
here is where I’m at right now…. And yes, I know, I forgot to get a right angle for the new pb return hose. Once I verify that it pumps correctly, I’ll go get one to route the hose properly!

Cheers!

 

[Jasonized]

I dont understand what you are saying. There is no way to change those circuits. They are an integral part of the tractor. The outlet for the power beyond is part of the 3pt valve.

not outlet for power beyond, but return line to tank from power beyond.

no worries, I basically understand what’s going on, so I’m good.
Have a nice day!

 

[TheOldHokie]

not outlet for power beyond, but return line to tank from power beyond.

no worries, I basically understand what’s going on, so I’m good.
Have a nice day!

Where is your new tank connection?

Dan

 

[Jasonized]

Where is your new tank connection?

Dan

I finally got all the connections on, and have to remake a hose. Yay.

My new configuration for PB is:

tank -> 3rdFunc -> Loader-> Diverter -> tank input from PB

So, basically, I took the PB output from the loader which was going to the PB input on the tank, and routed it to the rear for my new diverter valve. Then I routed the A position hose back to the PB input on the tank.
The B position (up) is routed to the power input side of the QC for the lane shark. The return line for the lane shark is now routed to a T fitting on the Tank output from the loader, into the tank.

I have to go get a new hose, and the aforementioned right angle fitting. This is for the PB return from the diverter valve. Sigh.

Cheers!

Oh, yes. The PB is upper left ('C' on the diagram) and the tank input is on the bottom right.

 

[TheOldHokie]

I finally got all the connections on, and have to remake a hose. Yay.

My new configuration for PB is:

tank -> 3rdFunc -> Loader-> Diverter -> tank input from PB

So, basically, I took the PB output from the loader which was going to the PB input on the tank, and routed it to the rear for my new diverter valve. Then I routed the A position hose back to the PB input on the tank.
The B position (up) is routed to the power input side of the QC for the lane shark. The return line for the lane shark is now routed to a T fitting on the Tank output from the loader, into the tank.

I have to go get a new hose, and the aforementioned right angle fitting. This is for the PB return from the diverter valve. Sigh.

Cheers!

You have ignored everything we discussed. Have fun.

Dan

 

[fried1765]

You have ignored everything we discussed. Have fun.

Dan

Maybe .....it will work ??

 

[TheOldHokie]

Maybe .....it will work???

Yes. It will work but not as well as it could. Certainly going to generate more heat and operating the 3pt with the motor running could be interesting.

EDIT: I just reread his post and he did it ascwe discussed. MEA CULPA

Dan

 

[Jasonized]

Well, gave it a try. Still need a longer hose and a 90 fitting, but tied everything down so I could try it.

works as expected! Kinda cool…. Went around and chopped up sap suckers and topped some tall bushes.

Heat has been mentioned in a number of other places as a concern.. I removed some of that by using a large diverter valve, and going directly to tank on return. Still goes through the 3rd and loader, of course, but from there to the tank is quick.

is there a gauge I can add to my hydraulics to measure temp, so I can watch it for awhile, or is that not really a concern?

Cheers!