hi everyone i have been working on school buses for a long time but not on the newer ones the vt365 we now have are something else i have servicemax i am still learning how to use it i hooked up to my bus a 2005 ih with a vt365 my driver told me it lost power then quit looking at service max i have 175 cranking rmp but servicemax say the fuel pressure should bulid to apx 750 psi i only get 325 psi any info on this issue would be very helpful Thanks
I think you mean ICP - injection control pressure. This is oil pressure generated by the high pressure pump that is used to fire the injectors. If ICP is way below the desired, you most likely have ICP leak. A common failure is at the branch tube fitting at the high pressure pump outlet. They have been redesigned from factory with a better fitting that comes in a kit from IH. Another common failure has been the high pressure pump itself. You need to do a leak test. My tech will be in tomorrow to provide a part number.
If it is a bad high pressure pump... BE SURE to check and change the screen Under the oil cooler. I have 3 2005/6 VT's that kicked high pressue pumps. also best to do a leak test on the high pressure oil system... Back to the screen.. Its a job to change EVERYTHING in the vee has to come out.. Turbo, Intake, oil filter assy, fuel filter assy, Everything. That screen protects the high pressure pump from debris in the oil. Also watch what brand oil filter you do use, some of the aftermarket filters are not quite as tall as OEM filters (or motorcraft). A lot of oil gets bypassed on those aftermarket filters. Also while you are in there you might as well change the EGR cooler. I'd hate to see that blow after you get that together, its more less insurance.
before you condemn the ICP pump or regulator, make sure the ICP sensor has not failed. very common. plus its out side of the valve cover so its easy to swap with a known good one or new one first.
Easy way to check the ICP sensor... Simply unplug it.. If it starts with it unpluged its bad. If not its something else. (the engine will run on defaults)
Just kidding. I have a 03 6.0 that just had all the HPOP stuff replaced and it ran for about 4 hours. Now its back to not starting again. I am fixing to put a half shell in the FICM and hope for the best.
well i went to santex and got the service and diagnostics manual that cost a pretty pennie the icp shows 616 apx at idle and that is what i get but as the rpm goes up my icp dose not go up properly it is low and at full power park brake set brake pedal depressed the engine will only go 1350 rpm i should get 2000 in less than 5 sec and my icp is only 980 psi (PS I DON'T LIKE THIS ENGINE it is fighting with me and it is winning !!!! i was told to remove the icr and inspect the screen on the end for debris or the screen missing?
If the screen on the IPR (mounted on the side of the High pressure pump) is busted or filled with debris. You aught to change the main screen under the oil cooler. Its broken.
OK here's where i am right now! i watched the computer during the many test the service manual put me and the bus through and i started to notice the icp actual and the desire'd did not always match so i pulled the ipr and checked it there was a couple of fragment on the screen but it was clean there was however a big crack in the screen so talking to one of the teck's from north east isd he said replace the ipr OK i did and now my pressures are much better and the bus will now get 100% power and i am not getting the injector faults now (i did have a panic attack when i retested i got a #5 injector open fault and the engine was missing badly turns out when i removed the turobo i unplugged the injector) i checked the turbo vane slider it moves freely so i am sending the unit to collage station Friday so far i don't see why not so now that i have more info i will reinspect my other unit with similar issues who knows it may be the same problem i really thank you for your help
Well If you had fragments and debris on your IPR valve chances are that your screen under your oil cooler is broken... I made the repair you did first bus lasted a month then it came back on the hook again..
vt365 cranks but no start
Posted - 02/18/2013 : 08:55:04 AM
