Ok here is the final rundown start to finish and what i found .it will be a long read.
Trip 1 boss man changed blown up primer pump
Trip 2 me , no power low power , found icp pressure sensor failing and possible ipr valve bad. Changed pressure sensor ,yep low pressure wouldnt go over 1750psi , changed ipr valve truck wakes up and runs good makes full pressure using cat et actuation test.
Next day phone call 1 blew up primer pump again, we left them a spare so they changed it but now a no start.
Trip 3 , me , first tackle fuel issue cant pump primer, remove dog box ( I HATE WORKING ON GMC MEDIUM DUTY TRUCKS),, Remove fitting in back of head try primer pumps fine ,see no debris in fitting must be stuck, install new fitting and hook line back up , retry primer it is now fine pumps fuel normaly. Tackle the no start huei pump making 257psi that wont work, thought high fuel pressure issues may have damaged huei pump inside changed huei pump truck started ran fine.
Phone call 2 next day truck quit again same field only made 2 rounds spreading chicken litter ,I was told primer came apart again i was like fml at this point they had a spare again so they changed it but still a no start.
Trip 4 me , talk to guy running truck he broke primer this time pulled it apart told him not to touch it that is not the problem with the teuxk quiting.
I had a theory but kept quite good thing cuz i was way off.
Step one for today double check fuel primer issue hook up pressure guage all is fine there. Hook up ET this time 280 psi all i getting out of huei pump, talk to cat they said check for a dumping injector and cut open oil filter. No oil coming thru injectors wondering if one has a cut o ring and its going into fuel, of course i cant tell in a fuel tank of red fuel. Cut open oil filter no aluminum chuncks from huei pump but metal is gray and sparkly , drained oil looked like i was draining an old differential, got a hand full of oil and found it has so much metal in it that it would jump up to my magnet, at this point i already new about the broken air filter housing but no one has any idea how long its been like that , get boss man he is willing to make the gamble so i proceed.
Pull injectors to check out o ring situation they were ok but ended up putting the new injectors in . Pulled high pressure oil galley plug at back of head and let drain and rinsed out with brakeclean best as possible . Installed new oil filter washed bottom of pan out with half a gallon of fresh oil and refilled , left galley plug out and cranked engine untill cleanish oil came from huei pump, buttoned everything up properly reprimed fuel and oil systems and topped off oil , check high pressure on crank still 280psi, removed ipr valve sprayed and blew out several times. Reinstalled cranked for about 5 seconds bam pressure went up to 1450 , tiny shot of ether got this worn out low on compression kitty cat going on a 75 degree day.
In conclusion i think i figured out the low oil pressure was due to the highly magnetic oil messing with the ipr valve especially in its higher duty cycle when they are spreading **** esentially clogging it up from the magnetism of the solenoid , there was that much iron in the oil.
They wouldnt let me leave till it made 4 trips into the field , i told them to dump the oil again after it warms up and i would look at a one of our sources for a good used engine, they only need it for 2 more days then it will come back to home farm but i am going to see if they will just bring it to the shop at the grading company instead so its near my stuff. So in conclusion i fixxed it but i didnt , its a wore out turd with a little fresh lipstick needing a transplant badly, new air filter housing is ordered so it will be good when it gets fixxed . Dang i should have done this on my computer not my phone, ohwell have a good one yall.