Pressure releif valve - front loader - Iseki 1240

[JerryG]

There should be a hydraulic manifold under the platform on the side of transmission housing. The PRV will be behind that manifold. This is the system relief valve. This will be right if it is like the mid size MFs that are built by Iseki.

 

[Marcle]

In the workshop manual I have, there's loads of torque settings for everything, but absolutely nothing on pressures!

 

[J_J]

I am not saying your are wrong, but most workshop manuals would have all the instructions for trouble shooting and setting the relief pressure.

Where did you put the gage to test pressure.

If you put it in a tee in the IN port of the FEL valve, it will show the pressure for any hyd component in the system.

What was the pressure with the FEL valve with the lever in the full up position?

What was the pressure with the 3pt in the full up position?

If you had your own flow meter and gage, you could test the pump flow and pressure.

You still have to know your pumps max pressure, and set any relief about 50 to 100 psi below that.

 

[Marcle]

I am not saying your are wrong, but most workshop manuals would have all the instructions for trouble shooting and setting the relief pressure.

Where did you put the gage to test pressure.

If you put it in a tee in the IN port of the FEL valve, it will show the pressure for any hyd component in the system.

What was the pressure with the FEL valve with the lever in the full up position?

What was the pressure with the 3pt in the full up position?

If you had your own flow meter and gage, you could test the pump flow and pressure.

You still have to know your pumps max pressure, and set any relief about 50 to 100 psi below that.

I hear what your saying about the manual, however I've been right through it and nothing. The trouble shooting page (not pages) is very basic.

The easiest place to put the gauge was the feed line to the fel up/lift line. The loader was under a heavy truck, so not at the end of stroke and the fel spool valve prv has been wound right down.

Moving the 3pt hyd lever to various positions made no difference. With regards to the other points, I'd need more written info to move forward.

A good point is that I've got a specialist comming this evening to have a look, but he admits he's more used to much larger machinery.

 

[Marcle]

There should be a hydraulic manifold under the platform on the side of transmission housing. The PRV will be behind that manifold. This is the system relief valve. This will be right if it is like the mid size MFs that are built by Iseki.

Below is a photo I took some time a go. I've taken 'D' out which is a prv, however now that I've got a manual (very basic on hydraulic info) it appears this may be a safety valve at the end of the hydraulic cylinder for the 3 pt linkage. 'A' controls the rate at which the 3 pt linkage raises and lowers.

'B' and 'C' are the flow and return pipe to the fel. Theses are plumbed to a manifold block. Are you saying there may be prv's under this block cover?

The unmarked arrow is to a shut off valve that feeds a quick release coupling on the wing.

 

[J_J]

Does your manual have a specifications page?

From the pictures, you have found both relief valves.

Can you provide flow path for your hyd?

The first relief valve in line will be the master relief, and the other relief can be set the same or lower.

Did the 3pt indicate the same pressure as the FEL.

Where was the gage when you did the 3pt pressure test?

The loader should be at the end of stroke, because the load will dictate the pressure. If you are only lifting half the potential weight, then you will read less pressure. The cyl must be at the end of stroke for max psi testing.

 

[Marcle]

I've now established the 'specified' pressures as being...
Pressure:1800 psi [124.1 bar]
Total flow:2.7 GPM [10.2 LPM]

However I'd still like help in knowing where the prv's are located please?

 

[J_J]

The relief valve should be located close by the IN port of any valve.

On the 3pt, it could be under a hex head screw.

 

[Marcle]

Thanks JJ,

I'm going to have to do some stripping down to see what I can find. Seems strange there's not a clear exploded diagram of the section of the system.

 

[Marcle]

Well... I've stripped hydraulic manifold off the side of the gearbox as shown in the photo below



Well the block is just a manifold, nothing more. looking down the holes on the side of the gearbox, there are no screws, all you can see is a port drilled off to the side and the bottom of a drilled hole. I even removed the bolt holding the pressure line from the pump to see if there was any screw within the threaded hole. nothing...

In another vain attempt to find a hidden adjustment screw or what ever, I took the pressed steel seat bracket off the top of the gearbox, but nothing.


Well I'm stuck again....