New loader valve not working properly

[jd4310man]

Just got done with a new valve installation on my loader. Im using the 10 gpm Brand LV series loader valve that uses one control stick to operate two spools. it has float position and regen mode. I installed a power beyond plug to feed an auxiliary valve down stream. All lines to loader are correctly connected, flow from pump comes in to the new valve and exits out threw the power beyond. It then feeds the aux valve downstream. I also installed a bypass hose to the return line as per instructions. My problem is the loader will raise normal but lowering it puts a load on the engine. The bucket also will put a load when moving in either direction. There is no load on loader to cause a strain to the engine, but from just moving it back and forth, it is causing a buildup of pressure when there is no load on hydraulics. The speed is not very fast so I don't think its because of too much flow, although im not exactly sure as im using a flow divider that is preset from factory. Any ideas what would cause this strain on the system with no load on system?

 

[Harry in Ky]

Better check your bypass/return hose. This needs a free return to sump. Sounds like you don't have that.

 

[J_J]

Re-set any QD's in the loader circuit.

Install a hyd gage so you monitor and trouble shoot the hyd system.

Check and see if any of your fittings are restrictors.

Is your 3pt lever in neutral?

 

[Fedup]

If the return hose from the new valve is correct, why would the three point lever have any effect on loader operation? Seems like pressure is stacking up because return oil flow has nowhere to go. Return oil goes to tank, not through power beyond to three point.

 

[J_J]

If the return hose from the new valve is correct, why would the three point lever have any effect on loader operation? Seems like pressure is stacking up because return oil flow has nowhere to go. Return oil goes to tank, not through power beyond to three point.

What would you think would happen if the 3pt was in the up position. If the lever is friction controlled, then the arms would be up and the valve relieving, and providing back pressure back up through all the valves. It will cause problems.

The 3pt when not is use, should be in neutral, so all pass through fluid will go directly to tank.

 

[jd4310man]

I was messing around with it today and I think the problem is with the fittings im using on the out ports to the loader cylinders. They seem to be causing a restriction of flow. I turned down the flow divider and it didnt stall the engine but the speed was too slow. I think im going to change to a larger size fitting at the loader valve and see what that does.

 

[J_J]

Some people make a mistake of buying restrictor fittings which will restrict flow.

Remove any fitting you suspect might be a restrictor fitting.

Similar to this.

http://agandfarmsupply.com/shop/art...ITTING.html?shop_param=cid=161&aid=1404R-8-8&

https://www.google.com/search?q=hyd...tricted-orifice-my-hydraulic-4.html;1200;1187

 

[Fedup]

Three point is downstream from loader valve isn't it? Loader valve is first in line for oil flow, so anything past the valve won't affect it's operation. The problem has to in the loader circuits or the return. Position of three point lever makes no difference.

 

[J_J]

Sure it will, just block the flow downstream for the PB and the return .

If the 3pt lever is up, you are already providing back pressure.

Stop the return flow, and the cyl will stop.

Install a gage in the IN port of the FEL valve and tell me what you see when the 3pt lever is full up.

Now, try working the FEL levers and tell me what you see.

 

[oldnslo]

3PH position,
A lot of what JJ is saying depends on the type of control on the 3PH. On my Kubota BX it operated like a directional valve where the lever was supposed to spring center allowing the flow to return to tank under no load. On my Branson 2400H it has position control so moving the 3PH lever moves the arms to a given position and then holds them close to this position. There is linkage on the lift arms that provides feed back to the directional valve that centers the spool and allows the oil to return to tank under no load. If the directional valve for the 3PH sticks or is held in the raise position it will create back pressure on your system.

Fedup is also correct that if the "Tank" line on the loader directional valve is connected properly, the position of the 3PH valve would have no bearing on how the loader valve operates since the return flow from the loader cylinders should be going directly to tank and NOT to the 3PH valve.

 

[jd4310man]

I took the machine to my local hydraulics shop and they seem to think that the problem is with the valve itself. All functions cause a strain on the pump except when the loader is raised. The valve has regen mode and when the loader goes into that mode is when it causes that strain. Also I have right angle fittings that come directly off the valve, that are smaller than what they should be. I think that they are 1/4" and the hose is 3/8". Could that cause the back pressure when the valve goes into regen mode? Also this valve has developed a leak from the one mounting hole. Could the valve be over pressurized enough to cause a fracture in the valve body? Even though the relief valve is working? The Valve is a Brand Loader valve and is at least 3 years old but was sold to me as new, so theirs no warranty on so im stuck with it. Im going to try to do a patch weld and hope it will buy me some time. My tractor is a Struck Magnatrac and I have added this valve along with the original one. There is no three point valve installed on machine.

 

[oldnslo]

Is the regen function for dumping the bucket or are you trying to raise the loader with regen?

 

[J_J]

Are you talking about a mono block valve with a crack in it?

If so, I can almost bet that someone deadheaded the valve OUT port or the PB port at some time.

If so, I don't think there is a fix for that.

Can you show a picture of the crack.

 

[jd4310man]

Its a very minute fracture and its right at the one mounting hole. This valve was unused for 3 years and more than likely its a lemon. Im going to order another valve as soon as they become available. This time it will have the manufactures warranty.

 

[jd4310man]

The biggest problem im having other than the loader valve leaking is when I use the valve, it puts a strain on the engine as I open the detentes to the loader. I took the valve apart and found no internal issues. I removed the check valves and it helped to eliminate strain on the down stroke of the loader but not the dump of the bucket. Im posting pics of the valve and its mount. I removed the power beyond plug and extra tank drain hose and that didn't do anything. I have to order a new valve, should I change to a higher gpm valve? I only plan on running 8gpm threw this thing. I also do not want or need a Regen valve. Is there a valve like this that is a plane jane single lever, two spool w float? Any recommendations as I lay out another $250-300 bucks?

 

[jd4310man]

Hear is the pics of the valve setup.

 

[J_J]

Here is a joystick loader valve.

If you don't want regen, don't push the lever to the far right.

2 SPOOL COMPACT 10 GPM JOYSTICK CONTROL VALVE

Two Spool Loader Valves LVT Series | Type 4-way, 4-pos. float LVT VALVE 2 SPL 220-132

What is the relief pressure, and is it working.

Are you sure all the hoses are connected correctly.

You need the PB adapter if there are valves downstream.

Did you install those valves?

I don't see but 6 hoses on the loader valve, so you are not using the PB port like you should.

I also don't see PB port on the remote valve either.

On the remote valve, are you using the one spool for a SA cyl?

 

[jd4310man]

J_J, I believe the system pressure is set at 2000 psi. I did have the PB adapter and extra hose attached, I was experimenting without the PB. The lower valve is what came with the machine. and the upper one is what I added. The lower valve goes strait to tank. I disconnected the upper joystick valve and hooked up the loader hoses to the old valve and the up and down are working properly, but the dump on the bucket is still giving me a problem. Also found out that the one bucket cylinder was causing a resistance. I replaced the seals in it and got a few of them backwards. I repowerd this machine with a Hatz air cooled diesel. I replaced the original two pump system with a bigger one pump system 1.78 cu in CESSNA 25502LSC HYD PUMP. I am using a prince adjustable flow divider 3/8" NPT 30 GPM ADJ PRIORITY DIVIDER VALVE RD537 to split the oil flow into two separate streams. Could running a larger single pump be causing me this problem? The up and down will work fine with the old valve. Im not sure yet but the one bucket cylinder may be the culprit.

 

[J_J]

How much flow is going to the priority circuit, and what does the priority circuit feed?

Did you swap the lift hose with the dump hose, and are the hoses connected correctly?

If using that pump, do you have 36 HP to run that pump at max?

It takes about 21 HP to run the pump at 1800 rpm

1.78 cu in displ/rev
3000 max RPM
Rated GPM at 2500 PSI:
21.3 @ Max RPM
12.5 @ 1800 RPM

 

[J_J]

Hear is the pics of the valve setup.

Looking at the upper valve, which hose is the hose from the pump/flow divider, the one with the blue stripe?

Which hose is the return hose from the upper valve?

The PB should be going to the lower valve IN port with the relief valve close by.

Here is the PB adapter for that valve.

BRAND POWER BEYOND KIT