Hydraulic Pressure Gauge and Pressure Reading Test

[Beltzington]

There are 4 hoses. bottom of valve ,top of valve, and two work hoses.

I believe your relief valve is the hex cap to the left side first picture.

If the bottom hose is the IN port, then that would be logical as the relief valve is normally close by the IN port on most valves.

JJ - You are correct, the top hose is the in port, which is where I have the pressure gage connected. As I mentioned earlier, I have removed the hex cap and fluid poured out, is that typical of a PRV?
Unfortunately when I ran out of diesel I apparently got air in the fuel lines and have not been able to start the engine to test the pressure under load. Going to be out of town a few days so it will be awhile before I can start troubleshooting.

 

[J_J]

You haven't shown us a picture of the relief valve.

A relief valve for the valve would normally have a spring and poppet to sit on the seat in the valve.

The spring and poppet will keep the valve closed, and will allow the hyd components to do their work building pressure dependent on load.

If the spring and poppet is missing, the pump flow is passing through the relief valve to tank. No pressure will be indicated and no work done.

There is such a thing as a relief valve that is a plug that will shut off the relief out flow and is used in CC valves when the relief is not needed.

Recommend you go to the chipper dealer and get the complete relief valve and then set it to specs.

Has this machine been running normally or did you just obtain it.

As far as air in the fuel lines, I just loosen the injector lines and let the air bleed out.

 

[Beltzington]

I was able to bleed the air from the filter and get the engine started. For testing the hydraulic pressure under load I put a 4" diameter 5' long piece of scrub oak and to my surprise it pulled it in and spit it out in about 10 seconds although the pressure gauge never indicated more than 200. Not sure what has changed since I first tested but I am committed to spend the few hundred dollars required to get this working. Need to buy several engine gauges, tach, temp, pressure and get them hooked up so I do not trash another engine. Once I can fully test the chipper I will replace or rebuild hydraulic parts as needed. Thanks to all for your input it has helped me very much.