OK the name Russell im new here and have a problem with my truck its an F350 with a 96 12 valve cummins and its popping back through the intake i tried and checked everything Well i changed the head gasket and it started....so i changed it again....still did it....Had a valve job done still...it had a bent push rod (my fault i missed the lifter) replaced it checked compression 475psi across the board thought i might have wiped out the cam pulled it "miked" it all lobes were like brand new new injectors.delivery valves tested fine its running on all 6 but pops loud through the intake and if you get into it you here detonation and it sounds like crap....idk im BAFFELED with this think im just outa ideas any ideas please let me know ...Thanks in advanced!!!! Russell -

 

slipped timing sounds like

 

that cummins doesnt like being in a ford, put it back in a dodge but really im not sure of your issure, but im sure somone here will help you out thers alot of knoledgeable people in this forum! good luck

 

slipped timing is exactly what it is, just experienced it

 

well how the hell did that happen????? it ran perfect then i just changed the head gasket and this happens idk how the pump timing slipped but it sounds petfect just a pop through the intake

 

its a taper shaft with no key so all that keeps the gear to the shaft is the torque on the nut.............any oil on the shaft during install will lessen the chance of it keeping time

 

believe me you havent the slightest idea how easy it is to slip it, i did mine at 2k rpm during break in after rebuild

 

i guess i just didnt mess with the thing all i did was change the head gasket ....what a joke now i have to pay some idiot to fix it i guess ...only thing i can think that made it happen is a couple of injectors that wouldnt pop off huh o well

 

it should realy cost anything to do, a diesel shop hear doesnt charge me a penny to use the dial guage on mine

 

well i loaded the damn thing on my semi and brought it to cummins to see if they can fix it....ill keep you guys posted