ISL9 330 CM2350

[mayhem1]

16 Freightliner with ISL9 330 CPL 4525 engine CM2350 came in on hook with fuel tank loaded with water. Almost pure water, a lot of it, not engine coolant. Enough that someone would have to have intentionally done this. 10 other trucks use main fuel supply and no other trucks are having issues. Drained tank completely, changed filters, and blew lines out. It ran good about half day and code 559 came up. Would not build fuel pressure, so replaced fuel pump assy. I had checked relief valve and sensor, even stuck a "test" one in to make sure. Did pressure test and was good. 29,200 lbs and dropped maybe 1000 in 5 minutes. Did injector test showed two that would not pass test point 1. So replaced all 6 because of all the water that had been through it. Passed leak test and injector test, but when test drive it almost immediately goes to code 559. Did another leak test and was fine, but did another injector test and two of the new one failed point 1. 2 out of 6 Cummins injectors bad? Or did water damage head? Fuel pressures are steady when comparing commanded vs measured.

[DVT873]

If this is the same as the the ISB did you replace the tubes between the injectors and the head? On the ISB they have edge filters inside. On ISB QuickServe says to "inspect". Other Cummins publications and people smarter than me say to always replace. I lost 2 injectors on #2 before learning this. Cut the tubes open and there was debri inside from what had to have been a prior pump failure. After replacing tubes no more injector failures. On a never ending upward learning curve. This site is a huge help to me. I'm new to Cummins. The EGR tuneup has straightened out several ISB after treatment issues. Everyone had been other places for DPF/DOC issues. Everyone had plugged EGRDP sensor ports. Several had face plugged DOC's. Have some video of a Ford 650 w ISB. After dropping the cans it smoked black like a freight train. Cleaned the ports, replaced the EGR valve and sensors. Back down the road, just a light puff on takeoff. No sensor codes on arrival. Hard to believe that a blocked 3/16 port can cause so much trouble. My thanks to Rawze and the site.

[mayhem1]

Yes it has those tubes. I had one seeping, so cleaned checked for cracks and it passed all tests in shop floor. I will try the tubes. It was strange as the fuel pressure actually went to negative numbers when it first gave me problems, replaced tank to primary filter line and that cleared that issue up. I just have a feeling that this overdose of H2O has damaged it deeper than I want to go. Rawze site is excellent. Tons of good info especially on egr/regen issues. Thanks for the input!