Thanks Joe! Don't know much on Cummins side but isn't the XPI fuel system a Cummins Fuel Systems product with Scania joint development and some of the midrange and big bore stuff is supplied by Bosch so maybe reason is different supplier strategy? The electrical connector looks like a Bosch Kompakt 1.1 on #3. On Delphi common rail, the rail pressure valve is a current controlled valve to keep it closed. If it gets unplugged or circuit issue, rail pressure goes to a limp home mode because has a spring loaded valve that will allow about 4500 PSI in rail. The ECM stores in memory the current required to keep valve closed, so usually you have to perform a reset in ECM is you replace the valve. The Delphi will actually use the release valve under certain conditions and runs self test during operation so it isn't just a safety relief valve. Thanks again, Steve.
Yes scania and other manufacturers do joint ventures on systems. They share engineers and it is a web if we tried to sort out who is who and who did what. Cummins was always smart enough to know their limitations in the moment and worked well with others. Im not sure of your age but when you are looking for something to do down the road you should start a channel or web to share info. Understanding what is happening and why is what makes a good troubleshooter,, tech, teacher. You have all that. I appreciate the comments and know that it helps many people. My friend and former colleague David Turner, God rest his soul, used to say "The world is round - it always comes back"
Loosen the line on the fuel rail coming from the fuel pump.
Thanks Joe! Don't know much on Cummins side but isn't the XPI fuel system a Cummins Fuel Systems product with Scania joint development and some of the midrange and big bore stuff is supplied by Bosch so maybe reason is different supplier strategy? The electrical connector looks like a Bosch Kompakt 1.1 on #3. On Delphi common rail, the rail pressure valve is a current controlled valve to keep it closed. If it gets unplugged or circuit issue, rail pressure goes to a limp home mode because has a spring loaded valve that will allow about 4500 PSI in rail. The ECM stores in memory the current required to keep valve closed, so usually you have to perform a reset in ECM is you replace the valve. The Delphi will actually use the release valve under certain conditions and runs self test during operation so it isn't just a safety relief valve. Thanks again, Steve.
Yes scania and other manufacturers do joint ventures on systems. They share engineers and it is a web if we tried to sort out who is who and who did what. Cummins was always smart enough to know their limitations in the moment and worked well with others.
Im not sure of your age but when you are looking for something to do down the road you should start a channel or web to share info. Understanding what is happening and why is what makes a good troubleshooter,, tech, teacher. You have all that.
I appreciate the comments and know that it helps many people.
My friend and former colleague David Turner, God rest his soul, used to say "The world is round - it always comes back"
When removing the relief valve , how do you release the pressure from the common rail tube ?
AS ALWAYS , Thank You !
Fellow viewer " @christalton9261 is correct. Loosen the high pressure fuel pump steel supply line at the rail.