Front diverter valve on L5740, work with regen?

cstamm81 · Jul 16, 2020

I am looking to add a diverter function to my front loader, on my 5740. I fully understand the difference between a diverter and a third function in both installation and function. What I can't be sure of, is whether or not a diverter will function properly on my machine. It looks like others have installed diverters on their 40 series Grands, and the knowledgeable hydraulic sites only list standard L series as having known issues with diverters. Upon getting ready to order a diverter, I noticed my loader control diagram sticker does indeed list a regen function on the curl / dump control valve. So, according to how I understand this, a diverter will NOT function properly. Can anyone definitively clear this up for me?

dstig1 · Jul 16, 2020

I have one on my L5240 on the curl/dump circuit for use with my grapple. Works perfectly. You can be confident it will work.

cstamm81 · Jul 17, 2020

perfect, thanks for the reply, I appreciate it.

LD1 · Jul 17, 2020

Not a simple answer because I dont know how the regen works on your valve.

I had a L3400 and pushing the stick to the right had TWO modes of dump. Regen, or non. Pushing the lever was 2-stage with a detent to push past....kinda like lower....and float when pushing the joystick foward.

Went to a MX5100. Only option was regen. No deten or a way to override detent.

If you dont understand how regen works....let me explain.
Instead of providing hydraulic power to the base end of the cylinder (to extend it) while allowing all the oil on the rod side a free pass pack to tank....regen supplies hydraulic power to BOTH ports. And in doing so.....the cylinder STILL EXTENDS. IT does so simply because of displacement. There is more surface area on the base end of the cylinder than the rod end. So equal pressure on both ends....there is still more force extending the cylinder, so it extends.

Lets say you have a 2" cylinder with a 1" rod. You have 3.14 square inches on the base of the piston trying to extend. @ 2500psi hydraulic pressure, that is 7850 pounds pushing the cylinder out. BUT, on the rod side.....since you subtract the area of the rod....you have 2.36 sq and at the same 2500psi that is 5900 pounds trying to retract the cylinder.

The net result is 1950 pounds of force extending the cylinder. So it still actually extends, just with less force. Which is NOT a problem when dumping the bucket on a tractor because that requires almost no force because of gravity. And actually the reason MFG's do this is because with a full bucket....gravity often works faster than the hydraulics when dumping...which causes the bucket to dump faster than it can fill with oil. And the result is when you dump....and have a cylinder half full of oil and the other half full of air....the bucket acts floppy. Regen, keeping pressure to both ports, stops this from happening and slows down the dump when you have a full bucket.

Now how all this applies to a diverter:
IF you plan on running a grapple off the diverter.....you bite force of the grapple will be significantly reduced if using a regen only valve. I found this out when installing a diverter on my MX. IT still works, sure....but at a great loss of power and efficiency. And if you are considering a snowplow like pickup trucks use, with a pair of single acting cylinders....forget it. Because if you provide pressure to BOTH single acting cylinders of the same size, its a stalemate and your plow wont angle when you push the stick to the right.

So....if you followed all of that....first and foremost you need to know if your valve is a regen only....or if it is has 2 dump options, one being non-regen.

But in either case....all is not lost. A diverter works fantastically on the lift-lower circuit. Which is what I did. And honestly, I find it alot more instinctive to push the lever forward and backwards to open and close the graple than I do left and right. And no loss of grapple power.

cstamm81 · Jul 17, 2020

LD1 said:
Not a simple answer because I dont know how the regen works on your valve.

I had a L3400 and pushing the stick to the right had TWO modes of dump. Regen, or non. Pushing the lever was 2-stage with a detent to push past....kinda like lower....and float when pushing the joystick foward.

Went to a MX5100. Only option was regen. No deten or a way to override detent.

If you dont understand how regen works....let me explain.
Instead of providing hydraulic power to the base end of the cylinder (to extend it) while allowing all the oil on the rod side a free pass pack to tank....regen supplies hydraulic power to BOTH ports. And in doing so.....the cylinder STILL EXTENDS. IT does so simply because of displacement. There is more surface area on the base end of the cylinder than the rod end. So equal pressure on both ends....there is still more force extending the cylinder, so it extends.

Lets say you have a 2" cylinder with a 1" rod. You have 3.14 square inches on the base of the piston trying to extend. @ 2500psi hydraulic pressure, that is 7850 pounds pushing the cylinder out. BUT, on the rod side.....since you subtract the area of the rod....you have 2.36 sq and at the same 2500psi that is 5900 pounds trying to retract the cylinder.

The net result is 1950 pounds of force extending the cylinder. So it still actually extends, just with less force. Which is NOT a problem when dumping the bucket on a tractor because that requires almost no force because of gravity. And actually the reason MFG's do this is because with a full bucket....gravity often works faster than the hydraulics when dumping...which causes the bucket to dump faster than it can fill with oil. And the result is when you dump....and have a cylinder half full of oil and the other half full of air....the bucket acts floppy. Regen, keeping pressure to both ports, stops this from happening and slows down the dump when you have a full bucket.

Now how all this applies to a diverter:
IF you plan on running a grapple off the diverter.....you bite force of the grapple will be significantly reduced if using a regen only valve. I found this out when installing a diverter on my MX. IT still works, sure....but at a great loss of power and efficiency. And if you are considering a snowplow like pickup trucks use, with a pair of single acting cylinders....forget it. Because if you provide pressure to BOTH single acting cylinders of the same size, its a stalemate and your plow wont angle when you push the stick to the right.

So....if you followed all of that....first and foremost you need to know if your valve is a regen only....or if it is has 2 dump options, one being non-regen.

But in either case....all is not lost. A diverter works fantastically on the lift-lower circuit. Which is what I did. And honestly, I find it alot more instinctive to push the lever forward and backwards to open and close the graple than I do left and right. And no loss of grapple power.

Amazing explanation, and believe it or not, I did keep up with it! Thanks so much for taking the time to explain it. I do have a 2 position dump function, regen and push past the detent normal dump. So, it sounds like it will work. And, I agree with you about using the raise and lower as the divert function. I read a post on this forum last night about this, and it does seem to make more sense to use the raise and lower, versus the dump and curl. Closing and opening a grapple, which is what it will be used for 90% of the time, makes more sense to push and pull a control versus using a side to side motion. Thanks again, I appreciate all of the collective knowledge on here!

TMGT · Jul 17, 2020

I've had a diverter on my B for about 9years, it has the 2 position regen valve.

There is no issue using the diverter with that system, yes it will have slightly less force in regen but you can just push past the regen if you need that little extra clamping force (I dont need it often and my grapple is used more than the bucket).
If your grapple is a good match to tractor then it shouldn't really matter.

I prefer the grapple control on the bucket curl as I've found it makes it easier to position since you can set the curl and use the lift to adjust while clamping.

Just make sure you hook the cylinders up the correct way, otherwise you'll be trying to figure out why they are going the same direction in both valve positions!

dstig1 · Jul 17, 2020

No, use the dump/curl circuit. It works perfectly fine on this tractor and allows you to grab with the grapple as you raise/lower. Trust me, it is intuitive. The grapple dumps (closes) when you dump, and curls (raises) when you curl the lever (with the button pushed). The grapple lid has the same exact motion as the bucket this way. That is why it is intuitive.

cstamm81 · Jul 20, 2020

Thanks for the replies gentlemen. I ordered the diverter valve, mounting plate, and Kubota style quick disconnect fittings. I'm going to mount the valve, then decide the best way to plumb it all in. I hate messy plumbing, so I'm waiting until I can decide what combination of adapters will work best.

Duly noted on the dump / curl circuit, looks like I have a decision to make!

While we're on it, if anyone has recessed the diverter button into the OEM loader grip, please send me pics. I'm going to attempt to shave off some of the rubber on the grip, and essentially recess the button into the handle. I could have went with a joystick handle with a trigger, but I feel I would have had to cut the loader valve handle shorter to make it work.