Hi guy's.. So I was given the task of finding out how the oil level rose up due to diesel in the crankcase.. I got this job after a few other issues occurred. I learned that it was smoking heavy, so they replaced the injectors. Well I found out yesterday , when I pulled #6 injector due to low temp on the cyl. by 50 degrees, it was rusted and not new... and a newbie was doing the repairs with no real guidance.. and he doesnt speak English.. I asked about the EUP's? The owner said #3 broke a bolt and moved.. new bolts but no new orings.. Ok, so I go back to that EUP, pull it and re-ring it.. They run the truck for part of the day, and oil level is 1" over full. So they give it back to me... I re-ring the other 6 EUP's and then check fuel pressure.. I did not check fuel pressure first, for my own reason's.. When I check fuel pressure, it is 125 PSI.. Today I changed the oil and filters, set the level to the full line, and put a new 60 PSI regulator on it.. I ran the engine and fuel pressure was almost 70 PSI.. No sweat.. So tomorrow they will run the truck to see how it does. I couldnt drive it for an hour, because I am building an ASET-C as well, and they didnt want me riding around... . So my question is... Barring a major issue like a crack somewhere.. How else could the crankcase get diesel contamination.. I figured the high fuel pressure was pushing it passed the lower EUP o-rings.. I don't get stumped often, but on this one, because 2 people were on it and one cant speak english.. I don't have the whole story.. I pulled the valve covers and ran the engine and watched the injector plugs for leaks and they were good. ok.. I will stop here and wait for some other ideas... Thanks guy's, Jojo