cat 3516 high ex temp eng derate

[SMOKED]

cat 793D, ENG derate issue .this is weird, low hour reman injectors, 10k hrs on engine, valve adjust done,3 of the four turbos new, truck keeps going into an engine derate while hauling240-280 ton, vims shows an ex temp split of 165 degrees, problem is when when you hook up cat et the truck meets all tests and only shows 20 deg ex temp split stalls at 1700 rpm, boost at 23-24 psi and 28 loaded up the ramp at 7mph, all new filters/screens, transfer pump at 70psi high idle and 45-50 stall,injector durations all close, manually cut out individual cylinders and all cylinders hitting strong, im about to replace the reman injectors with new cats,atmospheric is good,crankcase pressure good,air filter restriction at 4 inches new filters,left and right bank, boost press sensor not getting hung up, i am leaning on an injector getting stuck closed when pulling the ramp loaded but the solenoid is still firing so no fault codes, also replaced both ex probes, no abnormal smoke coolant temp normal, aftercooler temp normal, all i have left is a timing calibration and replace injectors, anyone have other ideas im getting stumped.:nail:

 

[revolutiondsl]

I work at the Cat plant in Lafayette Indiana where 3500s and 3600s are built and could probably talk to some of the guys in reman or the test cells. They run the engines for the first time and have probably seen about every issue out there.

 

[Bad Moose]

I would lean towards the reman injectors.

 

[mhuggler]

Do you have any codes/events or is it a silent derate?

 

[SMOKED]

sorry it took so long to get back, i ended up changing out all 8 injectors with new cats on the right bank,1,3,5,7,9,11,13,15, i would like to change the other bank too, but its hard to justify over 20k in injectors when 8 took care of the issue for now, i know there will most likely be problems with the others down the road but when gold is 1500.00 an ounce the machine needs to run even when its limping. thanks for the info.