Need Help on Hydraulic Issue

[KOLBRNR]

Hi Folks I am have an issue getting a diverter valve to work on my LA853 FEL.
I have a Kubota L5030 HSTC and I am trying to install a diverter valve for the curl/dump circuit to operate a power angle blade left and right.
The guy who is hooking it up has been working hydraulics for 24 years. The valve is solenoid operated from a button on the joystick.
The problem is this. When I pull the switch on the joystick the blade will angle left when I move the lever to curl position. This is correct. Now when I move the lever to the dump position the system locks up. I can hear the fluid going over the relief valve and the engine drops 200 rpm. If I switch the hoses the blade will go right when I move the lever to the curl position.
It seams as if the valve will only allow flow in one direction when diverted. We changed the valve and had the same result. I thought about one quick disconnect not opening properly and acting as a check valve but cant seam to gt it to work.

How can fluid only go in one direction to tank.
Has anyone had a similar trouble?

Russ

 

[bcp]

Got a photo or make/model number of the valve?

Bruce

 

[J_J]

Are you perhaps using the regen on the curl circuit.

There are one way solenoid diverter valve and two way solenoid diverter valves.

Single selector/diverter solenoid valve

Surplus Center - SAE 12 15 GPM 12 VDC HYDRA FORCE SELECTOR VALVE

Double selector/diverter valve. This one is or is similar to the solenoid valve used in grapple circuits.

Surplus Center - 12 VDC 13.2 GPM SAE 8 DOUBLE SELECTOR VALVE

If you used something similar to the double selector valve, and used DA cyl, then the solenoid is simply selecting which cyl is getting the curl fluid.

How about showing some pictures of what you have and how you connected things.

A hand drawn schematic would also work.

I have a single DA cyl on my dozer blade, and it works fine.

 

[KOLBRNR]

Do these help?
A1 pressure goes to A2 then T's off B1 goes to B2 then T's off. These run the curl dump by going straight through the valve.
When diverted A1 goes out the top to A3 and B1 goes out the top to B3.
The feed lines come from the lines on the FEL that cross from one side to the other that used to run the curl dump circuit. Only one fitting is used and the other one capped on each line.
Sounds simple but it only works in one direction. To the curl side.

Russ

 

[dstig1]

My guess - It is related to regen as JJ (the REAL expert) said. If you set up the angle cylinder the same way as the curl/dump cyls you will be fine, I bet. This means you need to T and use both ports of the angle cylinders. So T opposite ends together - farthest port on the right cyl with closest port on the left cyl, and vice versa.

BTW your other side is not capped, it is crossed-over. I can see the short hose at the back of the angle cylinders.

Maybe there is a way to bypass the regen on your loader stick (another position?) Hopefully JJ will be back along to give you the full scoop....

 

[SPYDERLK]

My guess - It is related to regen as JJ (the REAL expert) said. If you set up the angle cylinder the same way as the curl/dump cyls you will be fine, I bet. This means you need to T and use both ports of the angle cylinders. So T opposite ends together - farthest port on the right cyl with closest port on the left cyl, and vice versa.

BTW your other side is not capped, it is crossed-over. I can see the short hose at the back of the angle cylinders.

Maybe there is a way to bypass the regen on your loader stick (another position?) Hopefully JJ will be back along to give you the full scoop....

So, maybe youre just pushing the lever too far toward dump. If you just push it a little you wont hit the regen. Regen is internal to the valve. No extra plumbing needed - just dont operate the lever so far.
larry

 

[KOLBRNR]

My guess -

BTW your other side is not capped, it is crossed-over. I can see the short hose at the back of the angle cylinders.

Maybe there is a way to bypass the regen on your loader stick (another position?) Hopefully JJ will be back along to give you the full scoop....

What I meant was capped is the line on the loader. The blade is Teed to opposite ends of the cylinders.
I must say I really don't understand about the regen. If it can move to the left I don't understand how it can't move to the right. It's like something is hydro-locked.

Russ

 

[SPYDERLK]

Because regen applies pressure to both side of the cyl(s). They extend weakly[but fast] because the piston side has more area. Try holding the diverter switched and move the lever slowly toward dump.
larry

 

[KOLBRNR]

OK I can try that in the morning. 9:15pm here now. What has been happening is. when I move the lever to curl with the trigger pulled the blade goes left. However when I move the lever to dump it's like the blade kind of moves slightly to the right and then the tractor engine drops 200 rpm as the fluid goes across the relief valve. It could be that the blade only moves to the right due to the pressure coming off that side. Then when I move it to curl it will go left again with no trouble.
Why would the curl dump valve act differently from one movement to the other?
Why would this regen thing not happen when I move the lever to curl? It's the same valve on the loader so why act different?

 

[KOLBRNR]

Oh by the way JJ i will be passing through your neck of the woods in 2 weeks.
Going on a cruise out of Miami then going up to Waycross Georgia to visit my brother then back to Jacksonville to catch a flight home.

I hear it's hot already there.

Russ

 

[SPYDERLK]

Weight of the bucket aids dump. The regen can only work on an extending cylinder, so the valve does not have a regen circuit on curl because it would be futile [it would just cause a fast dump] . Regular slo dump can cavitate [form a bubble] on the piston side and can give floppy bucket after slow dump -- but sometimes you need to dump slo. When you dont, then dump fast using the far right regen position. This applies pressure to both sides of the cyl so no bubble.
larry

 

[J_J]

82 here today.

 

[KOLBRNR]

Weight of the bucket aids dump. The regen can only work on an extending cylinder, so the valve does not have a regen circuit on curl because it would be futile [it would just cause a fast dump] . Regular slo dump can cavitate [form a bubble] on the piston side and can give floppy bucket after slow dump -- but sometimes you need to dump slo. When you dont, then dump fast using the far right regen position. This applies pressure to both sides of the cyl so no bubble.
larry

I never thought about that. The weight of the bucket aiding in dumping.
I will give it a try tomorrow. Man I have gone to a lot of extra work trying to get this thing going. I am going to be quite annoyed if all I had to do was move the lever less. I never would have figured that one out.

Tomorrow we will see

42 here right now but tomorrow is going to be a whopping 59

Russ

 

[KOLBRNR]

OK guys I tried it. I think your right on the money about what is going on. When I move the lever to the dump position with the solenoid activated I can see both hydraulic lines flex as the pressure builds but the blade does not move. It does not matter how little I move the lever the blade will not angle right. Left to the curl position is not a problem.

Now that we know what is happening what pray tell do I do about it? How can I get around this regen situation? I don't want to have to buy a new tractor just to operate the blade.


Is there a better way to be doing this? Should I be teed into the power beyond and have a valve with 2 solenoids? 1 for left and 1 for right? I have a three function handle on the joystick so I could use the 2 buttons on top and disregard the trigger on the front.

Thanks so much for you help thus far. I don't know that much about hydraulics. That is why I hired a hydraulic guy to do this for me. However so far I am the one who is working on the solution.

Russ

 

[J_J]

Regen is only on the curl dump.

Someone else had the same problem, and I believe they either switched to a non-regen valve, or replaced the curl spool with a non-regen spool.

It is possible to add another independent two spool valve with PB and use that to control the blade, and use the regular loader valve for curl and lift.

 

[KOLBRNR]

Good morning JJ. Your an early riser like me.

I was wondering about the PB circuit. I don't know about a non regen valve. I will have to check into that. It would be easier at this point to use the curl dump as the lines are done already.

You don't know of a valve I could get do you?

Thanks I will keep you guys updated on how this goes.

Russ

 

[J_J]

Have you tried switching the diverter valve to the lift cyl circuit and using the lift lever to control the blade?

 

[KOLBRNR]

No but I can do that. It would only be more hose and fittings. I still have the original hoses so undoing it is easy. If there is no regen on that circuit then it would work, wouldn't it.

Good idea thanks JJ

I'm off to church so I will away from the computer for a bit.

Russ

 

[SPYDERLK]

Good morning JJ. Your an early riser like me.

I was wondering about the PB circuit. I don't know about a non regen valve. I will have to check into that. It would be easier at this point to use the curl dump as the lines are done already.

You don't know of a valve I could get do you?

Thanks I will keep you guys updated on how this goes.

Russ

Hey Russ. I have regular [power] dump and regen dump inherent in my valve - chosen by the amount I move the lever. Your valve sounds as if it only has regen dump. Pls try this: Press your bucket flat to the ground, center the valve, and then try to dump by pushing the lever rightward -- brakes OFF. Mine will tip the bucket forward and lift the tractor. Does yours at least almost lift it? It should I think, because I didnt know they made any loader valves that exclude the power dump. If it doesnt lift well go from there.
larry

 

[dstig1]

Well I think the solution is the same thing I posted earlier - T off of your lines for the angle cylinder and run hoses to both ends. Then they will behave exactly like the bucket cylinder and the problem should be solved. If you are feeding fluid to both ends of the cylinders it will not lock up. You have that small block on the plow bracket which would be a perfect point to T from. You just need to cross over these lines (T goes to far end of one, close end of the other). So a couple fittings and hoses, and you should be good.

Edit: BTW, the manual on my 723 loader says there is a non-regen position on the dump valve. There are 2 versions - the older one has the regular mode that is all the way to the right. So just barely opening it puts you in regen but full push is normal mode. The newer valve appears to be the exact opposite.