help hook up for 3 ph forklift

[wpala]

Hi so I bought this quite old 3 ph forklift attachment and to my surprise it has 3 quick connect houses my tractor has only 2outlets available on the back, the picture follows the first spool controls the top link no questions there the second spool is problem since the ram cylinder on the forklift part has only one connection on the bottom that would make it act as a single port cylinder so my question is what is the second hose with the quick connect for?? how can I make it in to 2 port system, valves are by star hydraulic can't find any info on them on the net any help would be greatly appreciated

Paul.W

 

[870boy]

Does the fork lift have side to side hydraulic movement?

 

[Tx Jim]

The fork lift should operate fine without attaching the quick disconnect to anything. The only thing I can think of for the quick disconnect to attach is a hose to sump for return oil but when spool is moved to let down forklift hyd oil would also be going to sump under hyd pump pressure.

 

[wpala]

No side movment

 

[wpala]

Someone also told me that this should work without hooking it up I was afraid I will damage the pump if there is no return and the pressure will keep building up but there is a pressure relief valve on the spool so it should be OK I will try that and let you know Thank You

Paul.W

 

[aczlan]

The fork lift should operate fine without attaching the quick disconnect to anything. The only thing I can think of for the quick disconnect to attach is a hose to sump for return oil but when spool is moved to let down forklift hyd oil would also be going to sump under hyd pump pressure.

That is how I see it as working. A way to drop the forks quicker.

Aaron Z

 

[wpala]

So I hooked up everything top link works perfect the carriage for the fork lift goes up but it stays there moving the spool handle backwards makes the hose jump a bit but nothing happens
Paul

 

[Xfaxman]

So I hooked up everything top link works perfect the carriage for the fork lift goes up but it stays there moving the spool handle backwards makes the hose jump a bit but nothing happens
Paul

Which hose jumps?

Need pictures. Show valve and hoses. What does the top of the lift cylinder have on it?

 

[Xfaxman]

I looked at your first picture, I think the quick disconnect has to go to the return line to the reservoir. You can put a tee with a matching QD any where in the return line.

How and where are the in/out hoses connected?

 

[Tx Jim]

So I hooked up everything top link works perfect the carriage for the fork lift goes up but it stays there moving the spool handle backwards makes the hose jump a bit but nothing happens
Paul

Did you attach the breakaway coupler to dump into sump on the hose that was on the valve??

 

[wpala]

I think You got it I took a quick connect (female) and was working the spool valve so there is a return flow through that hose but is low pressure it seams (weight of the fork lift pushes the oil) ,I'm afraid that if I put a tee the pressure circulating through the spool will prevent from dumping the oil I think I need to attache to "sump" where there is no pressure now where is that on the tractor ? do I need to run a new line to sump with the quick connect that would be the logical choice, I have a Kioti CK35

 

[Tx Jim]

Before you actually try to plumb the return hose to sump just temporarily stick hose in the hyd filler hole and see if forklift will lower correctly.

 

[wpala]

Yes it does I just tried it works perfectly, now to find a plug in the sump so I can plumb it
Paul

 

[Xfaxman]

I looked at your first picture, I think the quick disconnect has to go to the return line to the reservoir (sump). You can put a tee with a matching quick connect, any where in the return line.

How and where are the in/out hoses connected?

I think You got it I took a quick connect (female) and was working the spool valve so there is a return flow through that hose but is low pressure it seams (weight of the fork lift pushes the oil) ,I'm afraid that if I put a tee the pressure circulating through the spool will prevent from dumping the oil I think I need to attache to "sump" where there is no pressure now where is that on the tractor ? do I need to run a new line to sump with the quick connect that would be the logical choice, I have a Kioti CK35

There is no pressure in the return line past the last valve. What you have on that spool, is a single action valve.

It looks like there is a power beyond plug in the valve body. Does it have "PB" on it right below the out port? There is something there, just can't read it in the picture.

 

[Tx Jim]

It looks like there is a power beyond plug in the valve body. Does it have "PB" on it right below the out port? There is something there, just can't read it in the picture.

What difference would it make if the spool valve has a power beyond? The hose with the disconnect needs no pressure.

 

[Xfaxman]

What difference would it make if the spool valve has a power beyond? The hose with the disconnect needs no pressure.

If it has PB there would be pressure on the out line. If not he might be able to tee into the out line, depending what it is connected to.

 

[Tx Jim]

The hose that the QD is attached to has nothing to do with the bright cap(PB or OC/CC) in this photo as pressure on hose in question is controlled by the spool.

 

[J_J]

Are there any other valves past the valve you show?

If not, why not just tee into the OUT/return hose.

If there is another valve downstream, then use the PB port for downstream fluid and then tee into the the OUT/return hose.

 

[wpala]

Thank You all for the responses I appreciate them, here is what I think I know about all of this,
I have to turn the float switch on my tractor to run auxiliary hydraulic outlet , the control valve in question has 2 spools one controls a top link simple in and out second one hose is permanently screw on the bottom of the long cylinder that lifts the carriage of the forklift attachment, and the top line I figured is a dump line of the oil but the pressure of that line is not very high depending on the weight of the load on the fork lift, I ave tried to tee 2 return lines in tho back of the tractor no good, there is a pressure circulating in that line that will not allow to dump the oil, my understanding is that if the valves are closed the oil still circulates through the control valves (passing by waiting to be used) I have a spare quick connect female that I have attached to that hose in question and pointed in to my filling tube (where you add hydraulic oil) and was operating the valves and everything worked perfect goes up and down no problem, now I just have to find a place on the valve or tractor where there is a no pressure dump possible and is all good or I can change the piston on that valve to act as a single stage valve which will be hard since I can't find any info on the star hydraulic (maker of this control valve)
Paul.W

 

[Yellowhair42]

I have a forklift mast I adapted to my tractor.The raise/lower cylinder is power up,gravity down.When I first hooked to my tractor if I tried to power it down the top seal leaked.So I just put the return hose back to the reservior.I have a level plug and plumbed it to there.You have seemed to have figured this out already.Can you just put a tee where you have it now so it can return and you still have fill access?