Bump up lift capacity of L3400/LA463 Loader

[stoyan79]

Yes, I read the whole thread and know this is not the way it should be done, but it seems like it works, I won't mess with it until it causes issues. The bolt was very hard to turn, so I don't think its going anywhere.

Do you not realize that your relief valve is adjusted by shims and then you are supposed to torque down the cap nut to a certain torque and leave it there.

Somehow there is a misconception about how to adjust the relief pressure.

However, if you want to do it that way, then do so as it is your tractor.

Those shims come in different sizes and you can adjust the pressure using the right shims, with the cap nut torqued down correctly.

That kind of relief valve was not designed to adjust using the cap nut.

 

[McREBEL]

If the FEL has a relief, you can plug the gauge into one of the loader QD, which come out of the FEL work port. In order to see the pump pressure you move the lever to cause flow to the line the gauge is plugged into.

When the lever goes back to neutral, no pressure will show on the gauge, and if you active the 3pt, you will not show any pressure.

In order to show pressure at any time the tractor is running, the gauge needs to be in the flow path.

If you install a hyd gauge in a tee in the tube going to the FEL in port, the gauge will show any pressure developed by any cyl.

I looked through the PDF for that tractor many times and could not find but one relief valve which is in the FEL valve. .

Keep in mind that some tractors do not come setup for a loader, and have a relief valve just for the 3pt.

The loader and valve is add on and does contain a FEL relief valve.

Some times there are three relief valves, the FEL relief, the remote relief valve, and the 3pt.

Thanks. Between you guys and the owner's manual I am getting this figured out a little. I feel comfortable checking the pressure now at least. Just have to get the gauge. If the pressure is low it sounds like the first thing to do is to make sure the bolt is torqued properly. I understand not to adjust pressure with this bolt but only to make sure a loose bolt is not the cause if I have low pressure.

The B2920 manual states: "Do not connect attachments through the hydraulic motor to the [C] and [D] ports. If the control lever is moved to the Regeneration position (R1), the seals on the hydraulic motor will be damaged."

The C and D ports are for the bucket. Regeneration position (R1) is fast dump for the bucket. Any idea why the manual says this?

 

[J_J]

One reason might be that in regen mode, there is no return to tank as all fluid is sent to the dump mode.

A hyd motor needs a return to tank, and should be controlled using a motor spool valve.

Kubota tractors seem to have the regen in the first part of lever movement. Other loader valves have regen at the far right

It would be strange to operate a hyd motor off the curl circuits anyway.

There is usually an aux circuit for a hyd motor, a lever type motor spool valve or a solenoid motor spool valve.

 

[bumperm]

One reason might be that in regen mode, there is no return to tank as all fluid is sent to the dump mode.

A hyd motor needs a return to tank, and should be controlled using a motor spool valve.

Kubota tractors seem to have the regen in the first part of lever movement. Other loader valves have regen at the far right

It would be strange to operate a hyd motor off the curl circuits anyway.

There is usually an aux circuit for a hyd motor, a lever type motor spool valve or a solenoid motor spool valve.

A little off topic . . .

Interestingly, the install for the B2782B front mount snowblower uses the FEL controls, lift for lift, curl for hydraulic motor chute rotation, and either a diverter valve or 3rd function for chute deflection (I chose 3rd function so I can use it for other stuff, like a grapple etc.).

I questioned the dealer on the regen/hydraulic motor seal issue as curl (joy stick left/right) seems like the "natural" stick movement for chute rotation. The dealer checked with Kubota and their reps said not to worry about it. To be on the safe side, I don't linger in the regen area when rotating the chute - no problems so far.

 

[Tx Jim]

You guys keep trying to get me on something, and even if you do, I don't mind. He**, I make mistakes like everyone else.

McREBEL said he had a B2920, so I don't know what to tell you.

Look up the B2920 and tell me what you find.

I usually do my homework.[/QUOTE]

J_J
Sorry but I thought your statement of no relief on 3 pt was for the L3400. Actually I'm not attempting to "get you in an error" I just think info posted should be as correct as possible. . I just find it difficult to understand that a 3 pt hitch system has no relief valve. I'm not making an accusation but do you know what the function of the B2920 part outlined in red is?
Thanks,Jim
PS:The older I get the more mistakes I make

 

[J_J]

Does your hyd motor turn in regen or do you push the lever to the far right, to bypass regen?

Otherwise, the curl will work to control the hyd motor if not in regen.

 

[J_J]

You guys keep trying to get me on something, and even if you do, I don't mind. He**, I make mistakes like everyone else.

McREBEL said he had a B2920, so I don't know what to tell you.

Look up the B2920 and tell me what you find.

I usually do my homework.

J_J
Sorry but I thought your statement of no relief on 3 pt was for the L3400. Actually I'm not attempting to "get you in an error" I just think info posted should be as correct as possible. . I just find it difficult to understand that a 3 pt hitch system has no relief valve. I'm not making an accusation but do you know what the function of the B2920 part outlined in red is?
Thanks,Jim
PS:The older I get the more mistakes I make[/QUOTE]

What you have circled in red appears to be a check valve.

As far as no relief on the 3pt, consider this.

If the loader valves are built in and have a relief valve, and the flow path is from the pump to the loader valve, which has a relief.

Would a relief for the 3pt be necessary?

The basic tractor would probably have a 3pt relief valve, as most use the 3pt functions.

 

[Tx Jim]

J_J



What you have circled in red appears to be a check valve.

As far as no relief on the 3pt, consider this.

If the loader valves are built in and have a relief valve, and the flow path is from the pump to the loader valve, which has a relief.

Would a relief for the 3pt be necessary?

The basic tractor would probably have a 3pt relief valve, as most use the 3pt functions.

J_J
OK consider this if all B2920 tractors aren't equipped with a FEL then what protects the 3 pt if no relief valve is listed in parts? Does that indicate that ALL B2920's have a FEL installed at the factory or before they were sold new?
Thanks,Jim

 

[rswyan]

The data on your tractor is correct with a relief valve at the rear, and if you have remotes, you probably have another relief valve, and if you have a loader, then you probably have another relief valve.

Yup.

Go ahead and look at the PDF for the B2920 and tell me what you find.

I looked at it on the kubota.com website ... and then acknowledged you were in fact correct.

Your tractor probably came from the factory with only the 3pt relief, and has the tractor set relief pressure.

Yup - but only until one installs a PRV upstream (if the upstream PRV is set to a lower pressure)

The loader and rear remotes are add on.

Yup.

The other relief valves should be set the same, unless you want to set them different for some reason.

Well ... I've tweaked the loader up several hundred psi ... would be nice to set them all the same.

The issue with setting the the tractor relief (for the 3PH) is that you have to load the 3PH with enough weight that it will develop max pressure ... there's no easy way to deadhead it, due to the feedback lever at the top position.

Hopefully my ballast block will allow me to exactly that.

 

[rswyan]

J_J
OK consider this if all B2920 tractors aren't equipped with a FEL then what protects the 3 pt if no relief valve is listed in parts? Does that indicate that ALL B2920's have a FEL installed at the factory or before they were sold new?

It could be that they may not have the FEL ... but they do come with the control valve for it.