i have a 2006 freightliner m2 with the accert c9, and i am getting alot of fuel in the oil. i put dye in the fuel tank, i pulled the valve cover off and can see fuel around the #1 injector. i replace that one new and ran it, now i am getting fuel around #5 injector. has anyone had issues with the heads cracking with these engines?
sounds like injector cup O-rings.
If it's a while since it had injectors done you might be just as well pulling all 6 and replacing the seals on them. It may not be the injectors at all that are leaking, simply the seals. Also there are sleeves in the head for the injectors, maybe one or more of them could be giving trouble. ref 4 on the diagram below.
I have not heard about heads cracking but injector seals are a cheap easy start. If they haven't been done in a long time they can cause fuel in the oil or hard starting. If the injector cups are leaking you usually have fuel coming out the rad cap
Yea the injector o-rings were replaced 500 miles ago because of the same issue so one of my guys at the shop replaced the o-rings on all 6 but he had the wrong torque specs and over torqued them but backed them off as soon as he found the correct torque. Now it is having the same issue, and I don't want to be chasing my tail on the o-rings if it could be something else. Also I am not having issues with the coolant at this time.
By the sound of it injector cups are not your problem. I would try pressurizing the fuel system with the engine stopped and try to identify if the fuel is coming up past the orings or coming out of the injectors themselves. In the first case the fuel will be welling up out of the cylinder head, in the second it will be running down the injector body -subtle difference. Also when replacing injectors and/or seals there is usually a cleaning process required to get accumulated carbon off the cup so the new seals can seal correctly. When the seals were replaced 500 miles ago was that done...?