Where to place pressure gauge in simple open center system?

[lhfarm]

Yes, it will hold the load in the air, without a problem. This is a single action cylinder that does have a vent from the bottom of the cylinder to the tank.

 

[medic0648]

Was asking to verify the cylinder and valve weren't leaking down. Sounds like either an internal bypass in the valve not allowing sufficient pressure or the pump is worn.

 

[lhfarm]

Was asking to verify the cylinder and valve weren't leaking down. Sounds like either an internal bypass in the valve not allowing sufficient pressure or the pump is worn.

The first pump I found was worn out and couldn't be rebuilt. The current pump is off an IH C that was being parted out, so it may well be worn too. This was the same pump used by Newgren. I don't know of a source for a new or rebuilt pump. The cylinder was completely rebuilt and is the only part I'm sure is working. The installation document on our Web site is the only document I've ever seen on the lift.

There is one clue in the installation document - "No adjustment on valve is necessary as this has been set at the factory." I'm going to dig up some photos of when I had the valve apart for cleaning to see if I can figure out what can/is being adjusted.

Thanks,

 

[medic0648]

Do you have a hydraulic shop near you that could test it for flow and pressure? If not and you have a log splitter or tractor with oc hyd and a scv(or know someone that does) you could make a temporary adapter and try that. It would eliminate the valves being bad.

 

[J_J]

Was your vavle designed for your particular operation?

The relief valve could be set for a specific operation, but is it what you need. for the weight you want to lift?

Are you using your PS pump for the hyd, or is there another hyd pump just for the lift.

 

[lhfarm]

Was your vavle designed for your particular operation?

The relief valve could be set for a specific operation, but is it what you need. for the weight you want to lift?

Are you using your PS pump for the hyd, or is there another hyd pump just for the lift.

The crankshaft driven pump was what came with the original lift kit. The valve is original too. If you look at my avatar, that is the same lift installed on my 47 CJ2a. I was using a 12volt hydraulic pump at the time and it would lift implements with ease. When we (my son and I) decided to build a "show" jeep, we hunted and found (after about a 4 year search) an original bracket and pump (including the lovejoy). I immediately took the pump to a repair show and they determined that it was too worn to be used. So replaced it with an ebay IH C pump, which is the pump the manufacture used. Since I've had it working with an electric pump, I suspect the "new" pump may be worn to the point where it can't produce enough pressure. That would explain why I'm not getting much, if any reading on the gauge.

The only thing that makes me think there might be an issue with the valve was that it quit working 3 years ago, so I took it apart and cleaned it. But, most likely it is the pump.

I still have the electric pump and I could try to plumb it in and see what happens. Just not going to get that done before the show on Friday. At least I can show how the lift moves up an down and give small children a ride....

Thanks for all the help.

 

[lhfarm]

Are you sure you installed the gage in a tee in the IN port of the FEL valve?

Did you extend or retract any cyl to the max so the relief comes on.

If you have things connected correctly, you will show every psi the hyd system is developing.

If you did not see any pressure, then things are not connected correctly.

Rules are rules, and if the pump is good and the parts are good, then you will develop pressure.

Leave the gage installed, as it is a valuable tool for trouble shooting, and useful for monitoring the hyd system.

J J
I've been thinking about your note. While I'm sure the gauge is in front of the IN port of the FEL valve, I'm thinking the pump is running backwards. So things may not be connected correctly. The ports on the pump are the same size, only the manifold has different sized ports. That, in my mind, would explain the pressurized tank and NO reading on the gauge. I'm assuming the control valve could work, if not correctly, with things running backward.

Because of the mounting, it would be easier to reverse the manifold than try to rig up a way to test the flow direction. If I am wrong, and the pump is running correctly, could I do any damage by reversing they lines as a test?

Thanks for all the help.

 

[J_J]

Show us a picture of the valve.

The IN port is usually close to the relief valve.

The IN port is usually larger.

Some pumps can turn both CW, and CCW equally.

You can place the IN hose and OUT hose in two buckets with fluid , and see which port is the OUTPUT.

The pump should have an arrow or something to indicate direction.

If the ports are same size, the pump may be able to turn either direction.

This pump is reversible, and the ports are the same size.

http://www.surpluscenter.com/item.asp?item=9-10033&catname=hydraulic

 

[lhfarm]

Here is a string from when I rebuilt the valve a couple of years ago http://www.tractorbynet.com/forums/hydraulics/182148-need-help-rebuild-little-control.html

I actually did check the pump flow when I first mounted the pump and thought I had reversed the manifold. I may have to drain the system and try the buckets again.

Thanks,

 

[Xfaxman]

Are you using oil or hydraulic fluid? Some pumps are designed to use motor oil.