Isx wont start

[Rawze]

(01-04-2020 )Toddmsc Wrote:  I have def primed and cranked enough lol. I just finished up a head job on a friends triaxle and i did the same process as mine and it fired ran rough for 10 15 secs and smoothed right out.

I've pressurized the tanks and found nothing.

History on truck? Bought at 750k did clutch, rear main, and front structure gasket at 860k. Not a lick of other problems. Truck has always been super reliable.

have u cracked the return line open a bit on the front of the rail to see if the high pressure relief is leaking? / blowing fuel past it? - they are notorious for getting leaky or trash in them and cause starting and other issues if they are bad enough.

Also, those feed tubes going into the head for injectors, .. they are a one-time use (crush-fit), and cannot be swapped around once mated to an injector. -- If injectors have been out, and re-installed, or if someone has swapped them around, then they easily could be blowing fuel past them and into the return causing the rail pressure not to build fast enough during cranking. - they (and injectors too) can be tested with an old school diesel fuel pressure test set and an adapter... it is a life saver for the ISX, i don;t know why cummins does not have info on using one for the isx, or an adapter for one.. maybe want to sell injectors?...
ref: http://rawze.com/forums/showthread.php?t...56#pid2556





just some guesses. There are others on here who actually own those model engines that may have more ideas.